Export @required from src/widgets/framework.dart (#17208)

examples/flutter_gallery/lib/demo/animation/home.dart

@@ -7,7 +7,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
 

examples/flutter_gallery/lib/demo/animation/widgets.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 import 'sections.dart';

examples/flutter_gallery/lib/demo/colors_demo.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 const double kColorItemHeight = 48.0;

examples/flutter_gallery/lib/demo/material/bottom_app_bar_demo.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 class BottomAppBarDemo extends StatefulWidget {

examples/flutter_gallery/lib/demo/material/full_screen_dialog_demo.dart

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:intl/intl.dart';
 

examples/flutter_gallery/lib/demo/material/grid_list_demo.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 enum GridDemoTileStyle {

examples/flutter_gallery/lib/demo/shrine/shrine_order.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 import '../shrine_demo.dart' show ShrinePageRoute;

examples/flutter_gallery/lib/demo/shrine/shrine_page.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 import 'shrine_theme.dart';

examples/flutter_gallery/lib/demo/shrine/shrine_theme.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 class ShrineStyle extends TextStyle {

examples/flutter_gallery/lib/demo/typography_demo.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 class TextStyleItem extends StatelessWidget {

examples/flutter_gallery/lib/gallery/backdrop.dart

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

examples/flutter_gallery/lib/gallery/demos.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 import '../demo/all.dart';

examples/flutter_gallery/lib/gallery/options.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:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 import 'about.dart';

examples/flutter_gallery/lib/gallery/updater.dart

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 
 import 'package:url_launcher/url_launcher.dart';

packages/flutter/lib/src/cupertino/bottom_tab_bar.dart

@@ -4,7 +4,6 @@
 
 import 'dart:ui' show ImageFilter;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'colors.dart';

packages/flutter/lib/src/cupertino/dialog.dart

@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 import 'dart:ui' show ImageFilter;
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'colors.dart';

packages/flutter/lib/src/cupertino/page_scaffold.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'colors.dart';

packages/flutter/lib/src/cupertino/refresh.dart

@@ -4,7 +4,6 @@
 import 'dart:async';
 import 'dart:math';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter/services.dart';

packages/flutter/lib/src/cupertino/route.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:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';

packages/flutter/lib/src/cupertino/scrollbar.dart

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 // All values eyeballed.

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

@@ -5,7 +5,6 @@
 import 'dart:math' as math;
 import 'dart:ui' show lerpDouble;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';

packages/flutter/lib/src/cupertino/tab_scaffold.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 import 'bottom_tab_bar.dart';
 

packages/flutter/lib/src/cupertino/tab_view.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'route.dart';
@@ -152,4 +151,4 @@ class CupertinoTabView extends StatelessWidget {
     }());
     return result;
   }
-}
+}
\ No newline at end of file

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

@@ -9,7 +9,6 @@ import 'dart:math' as math show pi;
 import 'dart:ui' as ui show Paint, Path, Canvas;
 import 'dart:ui' show lerpDouble;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 // This package is split into multiple parts to enable a private API that is

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

@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 import 'package:flutter/rendering.dart';
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'arc.dart';

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

@@ -5,7 +5,6 @@
 import 'dart:collection' show Queue;
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 import 'package:vector_math/vector_math_64.dart' show Vector3;
 

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

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'colors.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 

packages/flutter/lib/src/material/checkbox_list_tile.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'checkbox.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/painting.dart';
 import 'package:flutter/rendering.dart';

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

@@ -5,7 +5,6 @@
 import 'dart:async';
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';

packages/flutter/lib/src/material/drawer_header.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'debug.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'button_theme.dart';

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

@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'colors.dart';

packages/flutter/lib/src/material/expansion_panel.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 

packages/flutter/lib/src/material/expansion_tile.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'colors.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/painting.dart';
 import 'package:flutter/widgets.dart';
 

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'scaffold.dart';

packages/flutter/lib/src/material/grid_tile.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 /// A tile in a material design grid list.

packages/flutter/lib/src/material/ink_decoration.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 

packages/flutter/lib/src/material/ink_highlight.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 

packages/flutter/lib/src/material/list_tile.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'colors.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:ui' show lerpDouble;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 

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

@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 import 'package:flutter/cupertino.dart';
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'theme.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 import 'package:flutter/rendering.dart';
 

packages/flutter/lib/src/material/radio.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 

packages/flutter/lib/src/material/radio_list_tile.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'list_tile.dart';

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

@@ -5,7 +5,6 @@
 import 'dart:async';
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'progress_indicator.dart';

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

@@ -5,7 +5,6 @@
 import 'dart:async';
 
 import 'package:flutter/cupertino.dart';
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'theme.dart';

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

@@ -5,7 +5,6 @@
 import 'dart:async';
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart' show timeDilation;

packages/flutter/lib/src/material/snack_bar.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'button_theme.dart';

packages/flutter/lib/src/material/stepper.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'button_theme.dart';

packages/flutter/lib/src/material/switch_list_tile.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'list_tile.dart';

packages/flutter/lib/src/material/tab_controller.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'constants.dart';

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

@@ -5,7 +5,6 @@
 import 'dart:async';
 import 'dart:ui' show lerpDouble;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
 

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

@@ -5,7 +5,6 @@
 import 'dart:collection';
 
 import 'package:flutter/cupertino.dart';
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';

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

@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 import 'dart:ui' show hashValues;
-import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'material_localizations.dart';

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

@@ -5,7 +5,6 @@
 import 'dart:async';
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';

packages/flutter/lib/src/material/two_level_list.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'colors.dart';

packages/flutter/lib/src/material/user_accounts_drawer_header.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:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';
 
 import 'colors.dart';

packages/flutter/lib/src/widgets/animated_cross_fade.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 
 import 'animated_size.dart';

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

@@ -5,7 +5,6 @@
 import 'package:collection/collection.dart' show binarySearch;
 
 import 'package:flutter/animation.dart';
-import 'package:flutter/foundation.dart';
 
 import 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/animated_size.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
 

packages/flutter/lib/src/widgets/animated_switcher.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:flutter/foundation.dart';
 import 'package:flutter/animation.dart';
 
 import 'basic.dart';

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

@@ -5,7 +5,6 @@
 import 'dart:async';
 import 'dart:ui' as ui show window;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 
 import 'banner.dart';

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

@@ -8,8 +8,6 @@
 
 import 'dart:async' show Future, Stream, StreamSubscription;
 
-import 'package:flutter/foundation.dart';
-
 import 'framework.dart';
 
 // Examples can assume:

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

@@ -4,8 +4,6 @@
 
 import 'dart:ui' show Color;
 
-import 'package:flutter/foundation.dart';
-
 import 'framework.dart';
 
 /// An interactive button within either material's [BottomNavigationBar]

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

@@ -5,8 +5,6 @@
 import 'dart:collection';
 import 'dart:developer' show Timeline; // to disambiguate reference in dartdocs below
 
-import 'package:flutter/foundation.dart';
-
 import 'basic.dart';
 import 'framework.dart';
 import 'media_query.dart';

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

@@ -2,8 +2,6 @@
 // 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 'automatic_keep_alive.dart';
 import 'basic.dart';
 import 'debug.dart';

packages/flutter/lib/src/widgets/drag_target.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:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
 

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

@@ -2,8 +2,6 @@
 // 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 'basic.dart';
 import 'focus_manager.dart';
 import 'framework.dart';

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

@@ -2,8 +2,6 @@
 // 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 'framework.dart';
 import 'navigator.dart';
 import 'will_pop_scope.dart';

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

@@ -14,6 +14,14 @@ import 'focus_manager.dart';
 
 export 'dart:ui' show hashValues, hashList;
 
+export 'package:flutter/foundation.dart' show
+  immutable,
+  mustCallSuper,
+  optionalTypeArgs,
+  protected,
+  required,
+  visibleForTesting;
+
 export 'package:flutter/foundation.dart' show FlutterError, debugPrint, debugPrintStack;
 export 'package:flutter/foundation.dart' show VoidCallback, ValueChanged, ValueGetter, ValueSetter;
 export 'package:flutter/foundation.dart' show DiagnosticLevel;

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

@@ -5,7 +5,6 @@ import 'dart:async';
 import 'dart:math' as math;
 
 import 'package:flutter/animation.dart';
-import 'package:flutter/foundation.dart';
 import 'package:flutter/physics.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 
 import 'basic.dart';

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

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

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

@@ -5,7 +5,6 @@
 import 'dart:async';
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/painting.dart';
 import 'package:flutter/physics.dart';

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

@@ -2,8 +2,6 @@
 // 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 'framework.dart';
 
 /// Signature for [Notification] listeners.

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

@@ -2,8 +2,6 @@
 // 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 'basic.dart';
 import 'framework.dart';
 import 'layout_builder.dart';

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

@@ -2,8 +2,6 @@
 // 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 'framework.dart';
 
 /// A [ValueKey] that defines where [PageStorage] values will be saved.

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

@@ -5,7 +5,6 @@
 import 'dart:async';
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/physics.dart';
 import 'package:flutter/rendering.dart';
 

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

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // 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 'basic.dart';
 import 'framework.dart';

packages/flutter/lib/src/widgets/preferred_size.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 
 import 'basic.dart';

packages/flutter/lib/src/widgets/scroll_notification.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:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 

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

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/physics.dart';
 import 'package:flutter/rendering.dart';

packages/flutter/lib/src/widgets/scroll_view.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 
 import 'basic.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 
 import 'basic.dart';

packages/flutter/lib/src/widgets/size_changed_layout_notifier.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 
 import 'framework.dart';

packages/flutter/lib/src/widgets/sliver_prototype_extent_list.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 
 import 'basic.dart';

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

@@ -2,8 +2,6 @@
 // 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 'basic.dart';
 import 'framework.dart';
 

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

@@ -4,7 +4,6 @@
 
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/scheduler.dart';

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

@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 import 'package:flutter/rendering.dart';
-import 'package:flutter/foundation.dart';
 import 'framework.dart';
 
 /// A rectangle upon which a backend texture is mapped.

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

@@ -4,7 +4,6 @@
 
 import 'dart:math' as math;
 
-import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:vector_math/vector_math_64.dart' show Matrix4;
 

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

@@ -2,8 +2,6 @@
 // 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 'framework.dart';
 
 /// Base class for stateful widgets that have exactly one inflated instance in

packages/flutter/lib/src/widgets/viewport.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:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 
 import 'basic.dart';