Reexport meta from foundation. (#6938)

examples/flutter_gallery/lib/gallery/app.dart

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart' show defaultTargetPlatform;
 import 'package:flutter/material.dart';
 import 'package:flutter/scheduler.dart' show timeDilation;
 

examples/flutter_gallery/lib/gallery/drawer.dart

@@ -4,6 +4,7 @@
 
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart' show defaultTargetPlatform;
 import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';

packages/flutter/lib/foundation.dart

@@ -18,3 +18,10 @@ export 'src/foundation/listenable.dart';
 export 'src/foundation/platform.dart';
 export 'src/foundation/print.dart';
 export 'src/foundation/synchronous_future.dart';
+
+export 'package:meta/meta.dart' show
+  checked,
+  mustCallSuper,
+  optionalTypeArgs,
+  protected,
+  required;

packages/flutter/lib/gestures.dart

@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 /// The Flutter gesture recognizers.
-/// 
+///
 /// To use, import `package:flutter/gestures.dart`.
 library gestures;
 

packages/flutter/lib/rendering.dart

@@ -51,5 +51,10 @@ export 'src/rendering/tweens.dart';
 export 'src/rendering/view.dart';
 export 'src/rendering/viewport.dart';
 
-export 'package:flutter/foundation.dart';
+export 'package:flutter/foundation.dart' show
+  VoidCallback,
+  ValueChanged,
+  ValueGetter,
+  ValueSetter;
+
 export 'package:vector_math/vector_math_64.dart' show Matrix4;

packages/flutter/lib/src/animation/animation_controller.dart

@@ -8,7 +8,6 @@ import 'dart:ui' as ui show lerpDouble;
 import 'package:flutter/foundation.dart';
 import 'package:flutter/physics.dart';
 import 'package:flutter/scheduler.dart';
-import 'package:meta/meta.dart';
 
 import 'animation.dart';
 import 'curves.dart';

packages/flutter/lib/src/animation/listener_helpers.dart

@@ -4,7 +4,7 @@
 
 import 'dart:ui' show VoidCallback;
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'animation.dart';
 

packages/flutter/lib/src/gestures/multidrag.dart

@@ -5,7 +5,7 @@
 import 'dart:async';
 import 'dart:ui' show Point, Offset;
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'arena.dart';
 import 'binding.dart';

packages/flutter/lib/src/gestures/recognizer.dart

@@ -7,7 +7,6 @@ import 'dart:collection';
 import 'dart:ui' show Point, Offset;
 
 import 'package:flutter/foundation.dart';
-import 'package:meta/meta.dart';
 
 import 'arena.dart';
 import 'binding.dart';

packages/flutter/lib/src/material/about.dart

@@ -5,7 +5,7 @@
 import 'dart:async';
 
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'app_bar.dart';
 import 'debug.dart';

packages/flutter/lib/src/material/arc.dart

@@ -5,8 +5,9 @@
 import 'dart:math' as math;
 import 'dart:ui' show hashValues, lerpDouble;
 
-import 'package:flutter/material.dart';
-import 'package:meta/meta.dart';
+import 'package:flutter/animation.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/painting.dart';
 
 // How close the begin and end points must be to an axis to be considered
 // vertical or horizontal.

packages/flutter/lib/src/material/bottom_navigation_bar.dart

@@ -5,8 +5,8 @@
 import 'dart:math' as math;
 import 'dart:collection' show Queue;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 import 'package:vector_math/vector_math_64.dart' show Vector3;
 
 import 'colors.dart';

packages/flutter/lib/src/material/button.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'colors.dart';
 import 'constants.dart';

packages/flutter/lib/src/material/checkbox.dart

@@ -4,9 +4,9 @@
 
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'constants.dart';
 import 'debug.dart';

packages/flutter/lib/src/material/date_picker.dart

@@ -5,11 +5,11 @@
 import 'dart:async';
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
 import 'package:intl/date_symbols.dart';
 import 'package:intl/intl.dart';
-import 'package:meta/meta.dart';
 
 import 'button_bar.dart';
 import 'button.dart';

packages/flutter/lib/src/material/drop_down.dart

@@ -4,9 +4,9 @@
 
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'colors.dart';
 import 'debug.dart';

packages/flutter/lib/src/material/expand_icon.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'colors.dart';
 import 'debug.dart';

packages/flutter/lib/src/material/expansion_panel.dart

@@ -2,9 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'expand_icon.dart';
 import 'mergeable_material.dart';

packages/flutter/lib/src/material/flat_button.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'button.dart';
 import 'theme.dart';

packages/flutter/lib/src/material/floating_action_button.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'colors.dart';
 import 'icon_theme_data.dart';

packages/flutter/lib/src/material/icon_button.dart

@@ -4,8 +4,8 @@
 
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'debug.dart';
 import 'icon.dart';

packages/flutter/lib/src/material/icon_theme.dart

@@ -3,9 +3,9 @@
 // found in the LICENSE file.
 
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'icon_theme_data.dart';
+import 'package:flutter/foundation.dart';
 import 'theme.dart';
 
 /// Controls the default color, opacity, and size of icons in a widget subtree.

packages/flutter/lib/src/material/material.dart

@@ -4,10 +4,9 @@
 
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
-import 'package:vector_math/vector_math_64.dart';
 
 import 'constants.dart';
 import 'shadows.dart';

packages/flutter/lib/src/material/mergeable_material.dart

@@ -2,9 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'dart:ui' show lerpDouble;
 

packages/flutter/lib/src/material/paginated_data_table.dart

@@ -4,7 +4,7 @@
 
 import 'dart:math' as math;
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 import 'package:flutter/rendering.dart';
 

packages/flutter/lib/src/material/popup_menu.dart

@@ -4,8 +4,8 @@
 
 import 'dart:async';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'constants.dart';
 import 'divider.dart';

packages/flutter/lib/src/material/radio.dart

@@ -2,9 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'constants.dart';
 import 'debug.dart';

packages/flutter/lib/src/material/raised_button.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'button.dart';
 import 'colors.dart';

packages/flutter/lib/src/material/slider.dart

@@ -4,10 +4,10 @@
 
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'colors.dart';
 import 'constants.dart';

packages/flutter/lib/src/material/snack_bar.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'button.dart';
 import 'flat_button.dart';

packages/flutter/lib/src/material/stepper.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'button.dart';
 import 'colors.dart';

packages/flutter/lib/src/material/switch.dart

@@ -2,11 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'colors.dart';
 import 'constants.dart';

packages/flutter/lib/src/material/tabs.dart

@@ -5,11 +5,11 @@
 import 'dart:async';
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/physics.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'app_bar.dart';
 import 'colors.dart';

packages/flutter/lib/src/material/theme.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'theme_data.dart';
 

packages/flutter/lib/src/material/time_picker.dart

@@ -5,9 +5,9 @@
 import 'dart:async';
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'button_bar.dart';
 import 'button.dart';

packages/flutter/lib/src/material/toggleable.dart

@@ -3,10 +3,10 @@
 // found in the LICENSE file.
 
 import 'package:flutter/animation.dart';
+import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
-import 'package:meta/meta.dart';
 
 import 'constants.dart';
 

packages/flutter/lib/src/material/two_level_list.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
-import 'package:meta/meta.dart';
 
 import 'colors.dart';
 import 'icon.dart';

packages/flutter/lib/src/material/typography.dart

@@ -2,10 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-
 import 'package:flutter/foundation.dart';
 import 'package:flutter/painting.dart';
-import 'package:meta/meta.dart';
 
 import 'colors.dart';
 

packages/flutter/lib/src/painting/box_painter.dart

@@ -5,8 +5,8 @@
 import 'dart:math' as math;
 import 'dart:ui' as ui show Image, Gradient, lerpDouble;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
-import 'package:meta/meta.dart';
 
 import 'basic_types.dart';
 import 'decoration.dart';

packages/flutter/lib/src/painting/decoration.dart

@@ -2,15 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
-import 'package:meta/meta.dart';
 
 import 'basic_types.dart';
 import 'edge_insets.dart';
 
+export 'package:flutter/services.dart' show ImageConfiguration;
+
 export 'basic_types.dart' show Point, Offset, Size;
 export 'edge_insets.dart' show EdgeInsets;
-export 'package:flutter/services.dart' show ImageConfiguration;
 
 // This group of classes is intended for painting in cartesian coordinates.
 

packages/flutter/lib/src/rendering/animated_size.dart

@@ -3,8 +3,8 @@
 // found in the LICENSE file.
 
 import 'package:flutter/animation.dart';
+import 'package:flutter/foundation.dart';
 import 'package:flutter/scheduler.dart';
-import 'package:meta/meta.dart';
 
 import 'box.dart';
 import 'object.dart';

packages/flutter/lib/src/rendering/auto_layout.dart

@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/cassowary.dart' as al; // "auto layout"
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'box.dart';
 import 'object.dart';

packages/flutter/lib/src/rendering/binding.dart

@@ -8,7 +8,6 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter/services.dart';
-import 'package:meta/meta.dart';
 
 import 'box.dart';
 import 'debug.dart';

packages/flutter/lib/src/rendering/box.dart

@@ -5,8 +5,9 @@
 import 'dart:math' as math;
 import 'dart:ui' as ui show lerpDouble;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
-import 'package:meta/meta.dart';
+
 import 'package:vector_math/vector_math_64.dart';
 
 import 'debug.dart';

packages/flutter/lib/src/rendering/custom_layout.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'box.dart';
 import 'object.dart';

packages/flutter/lib/src/rendering/flow.dart

@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/foundation.dart';
-import 'package:meta/meta.dart';
+
 import 'package:vector_math/vector_math_64.dart';
 
 import 'box.dart';

packages/flutter/lib/src/rendering/grid.dart

@@ -2,11 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
+
 import 'dart:math' as math;
 import 'dart:typed_data';
 
-import 'package:meta/meta.dart';
-
 import 'box.dart';
 import 'object.dart';
 import 'viewport.dart';

packages/flutter/lib/src/rendering/layer.dart

@@ -5,9 +5,9 @@
 import 'dart:ui' as ui show ImageFilter, Picture, SceneBuilder;
 import 'dart:ui' show Offset;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/painting.dart';
 import 'package:vector_math/vector_math_64.dart';
-import 'package:meta/meta.dart';
 
 import 'debug.dart';
 

packages/flutter/lib/src/rendering/node.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 /// An abstract node in a tree.
 ///

packages/flutter/lib/src/rendering/object.dart

@@ -9,7 +9,7 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/painting.dart';
 import 'package:flutter/scheduler.dart';
-import 'package:meta/meta.dart';
+
 import 'package:vector_math/vector_math_64.dart';
 
 import 'debug.dart';
@@ -18,9 +18,9 @@ import 'node.dart';
 import 'semantics.dart';
 import 'binding.dart';
 
+export 'package:flutter/foundation.dart' show FlutterError, InformationCollector;
 export 'package:flutter/gestures.dart' show HitTestEntry, HitTestResult;
 export 'package:flutter/painting.dart';
-export 'package:flutter/foundation.dart' show FlutterError, InformationCollector;
 
 /// Base class for data associated with a [RenderObject] by its parent.
 ///

packages/flutter/lib/src/rendering/proxy_box.dart

@@ -7,7 +7,7 @@ import 'dart:ui' as ui show ImageFilter;
 import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/painting.dart';
-import 'package:meta/meta.dart';
+
 import 'package:vector_math/vector_math_64.dart';
 
 import 'box.dart';

packages/flutter/lib/src/rendering/semantics.dart

@@ -6,7 +6,6 @@ import 'dart:ui' as ui;
 import 'dart:ui' show Rect, SemanticsAction, SemanticsFlags;
 import 'dart:typed_data';
 
-import 'package:meta/meta.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/painting.dart';
 import 'package:vector_math/vector_math_64.dart';

packages/flutter/lib/src/rendering/shifted_box.dart

@@ -4,7 +4,7 @@
 
 import 'dart:math' as math;
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'box.dart';
 import 'debug.dart';

packages/flutter/lib/src/rendering/stack.dart

@@ -5,7 +5,7 @@
 import 'dart:math' as math;
 import 'dart:ui' show lerpDouble, hashValues;
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'box.dart';
 import 'object.dart';

packages/flutter/lib/src/rendering/viewport.dart

@@ -4,7 +4,7 @@
 
 import 'dart:ui' as ui show window;
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 import 'package:vector_math/vector_math_64.dart';
 
 import 'box.dart';

packages/flutter/lib/src/scheduler/ticker.dart

@@ -5,7 +5,6 @@
 import 'dart:async';
 
 import 'package:flutter/foundation.dart';
-import 'package:meta/meta.dart';
 
 import 'binding.dart';
 

packages/flutter/lib/src/services/image_provider.dart

@@ -10,7 +10,6 @@ import 'dart:typed_data';
 
 import 'package:flutter/foundation.dart';
 import 'package:flutter/http.dart' as http;
-import 'package:meta/meta.dart';
 
 import 'asset_bundle.dart';
 import 'image_cache.dart';

packages/flutter/lib/src/services/image_stream.dart

@@ -5,8 +5,6 @@
 import 'dart:async';
 import 'dart:ui' as ui show Image;
 
-import 'package:meta/meta.dart';
-
 import 'package:flutter/foundation.dart';
 
 /// A [ui.Image] object with its corresponding scale.

packages/flutter/lib/src/services/raw_keyboard.dart

@@ -5,7 +5,6 @@
 import 'dart:async';
 
 import 'package:flutter/foundation.dart';
-import 'package:meta/meta.dart';
 
 import 'platform_messages.dart';
 

packages/flutter/lib/src/widgets/animated_cross_fade.dart

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'animated_size.dart';
 import 'basic.dart';

packages/flutter/lib/src/widgets/animated_size.dart

@@ -2,9 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/app.dart

@@ -5,8 +5,8 @@
 import 'dart:async';
 import 'dart:ui' as ui show window;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'banner.dart';
 import 'basic.dart';

packages/flutter/lib/src/widgets/auto_layout.dart

@@ -2,14 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'framework.dart';
 
 export 'package:flutter/rendering.dart' show
-    AutoLayoutRect,
-    AutoLayoutDelegate;
+  AutoLayoutRect,
+  AutoLayoutDelegate;
 
 /// A widget that uses the cassowary constraint solver to automatically size and position children.
 class AutoLayout extends MultiChildRenderObjectWidget {

packages/flutter/lib/src/widgets/banner.dart

@@ -4,7 +4,7 @@
 
 import 'dart:math' as math;
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/basic.dart

@@ -4,9 +4,9 @@
 
 import 'dart:ui' as ui show Image, ImageFilter;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
-import 'package:meta/meta.dart';
 
 import 'debug.dart';
 import 'framework.dart';
@@ -14,45 +14,45 @@ import 'framework.dart';
 export 'package:flutter/animation.dart';
 export 'package:flutter/painting.dart';
 export 'package:flutter/rendering.dart' show
-    Axis,
-    BoxConstraints,
-    CrossAxisAlignment,
-    CustomClipper,
-    CustomPainter,
-    FixedColumnCountGridDelegate,
-    FlexFit,
-    FlowDelegate,
-    FlowPaintingContext,
-    FractionalOffsetTween,
-    GridChildPlacement,
-    GridDelegate,
-    GridDelegateWithInOrderChildPlacement,
-    GridSpecification,
-    HitTestBehavior,
-    MainAxisAlignment,
-    MainAxisSize,
-    MaxTileWidthGridDelegate,
-    MultiChildLayoutDelegate,
-    Overflow,
-    PaintingContext,
-    PointerCancelEvent,
-    PointerCancelEventListener,
-    PointerDownEvent,
-    PointerDownEventListener,
-    PointerEvent,
-    PointerMoveEvent,
-    PointerMoveEventListener,
-    PointerUpEvent,
-    PointerUpEventListener,
-    RelativeRect,
-    ShaderCallback,
-    SingleChildLayoutDelegate,
-    TextOverflow,
-    ValueChanged,
-    ValueGetter,
-    ViewportAnchor,
-    ViewportDimensions,
-    ViewportDimensionsChangeCallback;
+  Axis,
+  BoxConstraints,
+  CrossAxisAlignment,
+  CustomClipper,
+  CustomPainter,
+  FixedColumnCountGridDelegate,
+  FlexFit,
+  FlowDelegate,
+  FlowPaintingContext,
+  FractionalOffsetTween,
+  GridChildPlacement,
+  GridDelegate,
+  GridDelegateWithInOrderChildPlacement,
+  GridSpecification,
+  HitTestBehavior,
+  MainAxisAlignment,
+  MainAxisSize,
+  MaxTileWidthGridDelegate,
+  MultiChildLayoutDelegate,
+  Overflow,
+  PaintingContext,
+  PointerCancelEvent,
+  PointerCancelEventListener,
+  PointerDownEvent,
+  PointerDownEventListener,
+  PointerEvent,
+  PointerMoveEvent,
+  PointerMoveEventListener,
+  PointerUpEvent,
+  PointerUpEventListener,
+  RelativeRect,
+  ShaderCallback,
+  SingleChildLayoutDelegate,
+  TextOverflow,
+  ValueChanged,
+  ValueGetter,
+  ViewportAnchor,
+  ViewportDimensions,
+  ViewportDimensionsChangeCallback;
 
 // PAINTING NODES
 

packages/flutter/lib/src/widgets/binding.dart

@@ -7,11 +7,11 @@ import 'dart:developer' as developer;
 import 'dart:ui' as ui show window;
 import 'dart:ui' show AppLifecycleState, Locale;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter/services.dart';
-import 'package:meta/meta.dart';
 
 import 'app.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/clamp_overscrolls.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'framework.dart';
 import 'scrollable.dart';

packages/flutter/lib/src/widgets/container.dart

@@ -2,9 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/painting.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/dismissable.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/drag_target.dart

@@ -2,10 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'binding.dart';

packages/flutter/lib/src/widgets/editable.dart

@@ -4,9 +4,9 @@
 
 import 'dart:async';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart' show RenderEditable, SelectionChangedHandler, RenderEditablePaintOffsetNeededCallback;
 import 'package:flutter/services.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'focus.dart';

packages/flutter/lib/src/widgets/focus.dart

@@ -4,7 +4,7 @@
 
 import 'dart:async';
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/form.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'framework.dart';
 

packages/flutter/lib/src/widgets/framework.dart

@@ -10,11 +10,11 @@ import 'debug.dart';
 
 import 'package:flutter/rendering.dart';
 import 'package:flutter/foundation.dart';
-import 'package:meta/meta.dart';
 
 export 'dart:ui' show hashValues, hashList;
-export 'package:flutter/rendering.dart' show RenderObject, RenderBox, debugPrint;
 export 'package:flutter/foundation.dart' show FlutterError;
+export 'package:flutter/foundation.dart' show VoidCallback, ValueChanged, ValueGetter, ValueSetter;
+export 'package:flutter/rendering.dart' show RenderObject, RenderBox, debugPrint;
 
 // KEYS
 

packages/flutter/lib/src/widgets/heroes.dart

@@ -4,7 +4,6 @@
 
 import 'dart:collection';
 
-import 'package:meta/meta.dart';
 import 'package:flutter/foundation.dart';
 
 import 'basic.dart';

packages/flutter/lib/src/widgets/image.dart

@@ -4,18 +4,18 @@
 
 import 'dart:io' show File, Platform;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'framework.dart';
 import 'media_query.dart';
 
 export 'package:flutter/services.dart' show
-    AssetImage,
-    ExactAssetImage,
-    NetworkImage,
-    FileImage;
+  AssetImage,
+  ExactAssetImage,
+  NetworkImage,
+  FileImage;
 
 /// Creates an [ImageConfiguration] based on the given [BuildContext] (and
 /// optionally size).

packages/flutter/lib/src/widgets/implicit_animations.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 import 'package:vector_math/vector_math_64.dart';
 
 import 'basic.dart';
@@ -239,7 +239,7 @@ class AnimatedContainer extends ImplicitlyAnimatedWidget {
     this.width,
     this.height,
     Curve curve: Curves.linear,
-    @required Duration duration
+    @required Duration duration,
   }) : super(key: key, curve: curve, duration: duration) {
     assert(decoration == null || decoration.debugAssertIsValid());
     assert(foregroundDecoration == null || foregroundDecoration.debugAssertIsValid());
@@ -383,7 +383,7 @@ class AnimatedPositioned extends ImplicitlyAnimatedWidget {
     this.width,
     this.height,
     Curve curve: Curves.linear,
-    @required Duration duration
+    @required Duration duration,
   }) : super(key: key, curve: curve, duration: duration) {
     assert(left == null || right == null || width == null);
     assert(top == null || bottom == null || height == null);
@@ -518,7 +518,7 @@ class AnimatedOpacity extends ImplicitlyAnimatedWidget {
     this.child,
     this.opacity,
     Curve curve: Curves.linear,
-    @required Duration duration
+    @required Duration duration,
   }) : super(key: key, curve: curve, duration: duration) {
     assert(opacity != null && opacity >= 0.0 && opacity <= 1.0);
   }
@@ -575,7 +575,7 @@ class AnimatedDefaultTextStyle extends ImplicitlyAnimatedWidget {
     @required this.child,
     @required this.style,
     Curve curve: Curves.linear,
-    @required Duration duration
+    @required Duration duration,
   }) : super(key: key, curve: curve, duration: duration) {
     assert(style != null);
     assert(child != null);

packages/flutter/lib/src/widgets/layout_builder.dart

@@ -5,8 +5,8 @@
 import 'debug.dart';
 import 'framework.dart';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 /// The signature of the [LayoutBuilder] builder function.
 typedef Widget LayoutWidgetBuilder(BuildContext context, BoxConstraints constraints);

packages/flutter/lib/src/widgets/lazy_block.dart

@@ -5,7 +5,7 @@
 import 'dart:math' as math;
 
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/locale_query.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'framework.dart';
 

packages/flutter/lib/src/widgets/media_query.dart

@@ -4,7 +4,7 @@
 
 import 'dart:ui' as ui;
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'framework.dart';
@@ -107,7 +107,7 @@ class MediaQuery extends InheritedWidget {
   MediaQuery({
     Key key,
     @required this.data,
-    @required Widget child
+    @required Widget child,
   }) : super(key: key, child: child) {
     assert(child != null);
     assert(data != null);

packages/flutter/lib/src/widgets/navigator.dart

@@ -4,8 +4,8 @@
 
 import 'dart:async';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'binding.dart';

packages/flutter/lib/src/widgets/orientation_builder.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'framework.dart';
@@ -29,7 +29,7 @@ class OrientationBuilder extends StatelessWidget {
   /// The [builder] argument must not be null.
   OrientationBuilder({
     Key key,
-    @required this.builder
+    @required this.builder,
   }) : super(key: key) {
     assert(builder != null);
   }

packages/flutter/lib/src/widgets/overlay.dart

@@ -5,9 +5,9 @@
 import 'dart:async';
 import 'dart:collection';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'debug.dart';

packages/flutter/lib/src/widgets/page_storage.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'framework.dart';
 

packages/flutter/lib/src/widgets/routes.dart

@@ -4,7 +4,7 @@
 
 import 'dart:async';
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'focus.dart';

packages/flutter/lib/src/widgets/scroll_behavior.dart

@@ -6,7 +6,6 @@ import 'dart:math' as math;
 
 import 'package:flutter/foundation.dart';
 import 'package:flutter/physics.dart';
-import 'package:meta/meta.dart';
 
 import 'scroll_simulation.dart';
 

packages/flutter/lib/src/widgets/scroll_configuration.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
 import 'package:flutter/foundation.dart';
 
 import 'framework.dart';

packages/flutter/lib/src/widgets/scrollable.dart

@@ -6,10 +6,10 @@ import 'dart:async';
 import 'dart:math' as math;
 import 'dart:ui' as ui show window;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/physics.dart';
 import 'package:flutter/scheduler.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'clamp_overscrolls.dart';

packages/flutter/lib/src/widgets/scrollable_grid.dart

@@ -5,8 +5,8 @@
 import 'dart:math' as math;
 
 import 'package:collection/collection.dart' show lowerBound;
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'framework.dart';
 import 'scroll_configuration.dart';

packages/flutter/lib/src/widgets/scrollable_list.dart

@@ -4,8 +4,8 @@
 
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'framework.dart';
 import 'scroll_configuration.dart';

packages/flutter/lib/src/widgets/status_transitions.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/table.dart

@@ -4,23 +4,23 @@
 
 import 'dart:collection';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'debug.dart';
 import 'framework.dart';
 import 'image.dart';
 
 export 'package:flutter/rendering.dart' show
-    FixedColumnWidth,
-    FlexColumnWidth,
-    FractionColumnWidth,
-    IntrinsicColumnWidth,
-    MaxColumnWidth,
-    MinColumnWidth,
-    TableBorder,
-    TableCellVerticalAlignment,
-    TableColumnWidth;
+  FixedColumnWidth,
+  FlexColumnWidth,
+  FractionColumnWidth,
+  IntrinsicColumnWidth,
+  MaxColumnWidth,
+  MinColumnWidth,
+  TableBorder,
+  TableCellVerticalAlignment,
+  TableColumnWidth;
 
 /// A horizontal group of cells in a [Table].
 ///

packages/flutter/lib/src/widgets/text.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/text_selection.dart

@@ -2,9 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'container.dart';

packages/flutter/lib/src/widgets/ticker_provider.dart

@@ -4,7 +4,6 @@
 
 import 'package:flutter/foundation.dart';
 import 'package:flutter/scheduler.dart';
-import 'package:meta/meta.dart';
 
 import 'framework.dart';
 

packages/flutter/lib/src/widgets/transitions.dart

@@ -4,7 +4,7 @@
 
 import 'dart:math' as math;
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 import 'package:vector_math/vector_math_64.dart' show Matrix4;
 
 import 'basic.dart';

packages/flutter/lib/src/widgets/unique_widget.dart

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'framework.dart';
 

packages/flutter/lib/src/widgets/virtual_viewport.dart

@@ -4,8 +4,8 @@
 
 import 'dart:math' as math;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
-import 'package:meta/meta.dart';
 
 import 'basic.dart';
 import 'debug.dart';

packages/flutter/lib/widgets.dart

@@ -2,8 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-/// The Flutter widget framework.
-///
+/// The Flutter widgets framework.
 ///
 /// To use, import `package:flutter/widgets.dart`.
 library widgets;
@@ -64,5 +63,4 @@ export 'src/widgets/transitions.dart';
 export 'src/widgets/unique_widget.dart';
 export 'src/widgets/virtual_viewport.dart';
 
-export 'package:flutter/foundation.dart';
 export 'package:vector_math/vector_math_64.dart' show Matrix4;

packages/flutter/test/rendering/rendering_tester.dart

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';

packages/flutter/test/widgets/image_resolution_test.dart

@@ -6,6 +6,7 @@ import 'dart:async';
 import 'dart:typed_data';
 import 'dart:ui' as ui show Image;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';

packages/flutter/test/widgets/image_test.dart

@@ -5,10 +5,11 @@
 import 'dart:async';
 import 'dart:ui' as ui show Image;
 
-import 'package:flutter_test/flutter_test.dart';
-import 'package:flutter/services.dart';
+import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
+import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
 
 void main() {
   testWidgets('Verify Image resets its RenderImage when changing providers', (WidgetTester tester) async {

packages/flutter/test/widgets/scroll_behavior_test.dart

@@ -2,8 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:flutter_test/flutter_test.dart';
+import 'package:flutter/foundation.dart' show defaultTargetPlatform;
 import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
 
 class TestScrollConfigurationDelegate extends ScrollConfigurationDelegate {
   TestScrollConfigurationDelegate(this.flag);

packages/flutter/test/widgets/state_setting_in_scrollables_test.dart

@@ -2,8 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:flutter_test/flutter_test.dart' hide TypeMatcher;
+import 'package:flutter/foundation.dart' show defaultTargetPlatform;
 import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart' hide TypeMatcher;
 
 class Foo extends StatefulWidget {
   @override

packages/flutter_test/lib/src/all_elements.dart

@@ -2,8 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:meta/meta.dart';
-
+import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 /// Provides an iterable that efficiently returns all the elements