Remove use of activity.mojom (#6317)

Instead, we now interact with the system navigator via SystemNavigator.

bin/internal/engine.version

-50f1b8d9ca29e2fe70cd9012c5e3bf6eff29ce91
+da96a8bddda72f14b02a0afda871d126dfebdb17

examples/layers/services/start_activity.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/widgets.dart';
-import 'package:flutter/services.dart';
-
-void main() {
-  runApp(new GestureDetector(
-    onTap: () {
-      Intent intent = new Intent()
-        ..action = 'android.intent.action.VIEW'
-        ..url = 'http://flutter.io/';
-      activity.startActivity(intent);
-    },
-    child: new Container(
-      decoration: const BoxDecoration(
-        backgroundColor: const Color(0xFF006600)
-      ),
-      child: new Center(
-        child: new Text('Tap to launch a URL!')
-      )
-    )
-  ));
-}

packages/flutter/lib/services.dart

@@ -14,7 +14,6 @@
 /// Flutter library.
 library services;
 
-export 'src/services/activity.dart';
 export 'src/services/asset_bundle.dart';
 export 'src/services/binding.dart';
 export 'src/services/clipboard.dart';
@@ -30,5 +29,6 @@ export 'src/services/path_provider.dart';
 export 'src/services/platform_messages.dart';
 export 'src/services/shell.dart';
 export 'src/services/system_chrome.dart';
+export 'src/services/system_navigator.dart';
 export 'src/services/system_sound.dart';
 export 'src/services/url_launcher.dart';

packages/flutter/lib/src/services/activity.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 'dart:ui';
-
-import 'package:flutter_services/activity.dart';
-
-import 'shell.dart';
-
-export 'package:flutter_services/activity.dart' show Activity, Intent, ComponentName, StringExtra;
-
-
-// Dart wrapper around Activity mojo service available in Flutter on Android.
-//
-// Most clients will want to use these methods instead of the activity service
-// directly.
-
-// The constants below are from
-// http://developer.android.com/reference/android/content/Intent.html
-
-/// Open a document into a new task rooted at the activity launched by
-/// this Intent.
-///
-/// See Android's Intent.FLAG_ACTIVITY_NEW_DOCUMENT.
-const int NEW_DOCUMENT = 0x00080000; // ignore: constant_identifier_names
-
-/// Start a new task on this history stack.
-///
-/// See Android's Intent.FLAG_ACTIVITY_NEW_TASK.
-const int NEW_TASK = 0x10000000; // ignore: constant_identifier_names
-
-/// Create a new task and launch an activity into it.
-///
-/// See Android's Intent.FLAG_ACTIVITY_MULTIPLE_TASK.
-const int MULTIPLE_TASK = 0x08000000; // ignore: constant_identifier_names
-
-ActivityProxy _initActivityProxy() {
-  return shell.connectToApplicationService('mojo:android', Activity.connectToService);
-}
-
-final ActivityProxy _activityProxy = _initActivityProxy();
-
-/// A singleton for interacting with the current Android activity.
-final Activity activity = _activityProxy;
-
-Color _cachedPrimaryColor;
-String _cachedLabel;
-
-/// Sets the TaskDescription for the current Activity.
-/// The color, if provided, must be opaque.
-void updateTaskDescription({ String label, Color color }) {
-  assert(color == null || color.alpha == 0xFF);
-  if (_cachedPrimaryColor == color && _cachedLabel == label)
-    return;
-
-  _cachedPrimaryColor = color;
-  _cachedLabel = label;
-
-  TaskDescription description = new TaskDescription()
-    ..label = label
-    ..primaryColor = color?.value ?? 0;
-
-  _activityProxy.setTaskDescription(description);
-}

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

@@ -24,7 +24,7 @@ class HapticFeedback {
   static Future<Null> vibrate() async {
     await PlatformMessages.sendJSON('flutter/platform', <String, dynamic>{
       'method': 'HapticFeedback.vibrate',
-      'args': <Null>[],
+      'args': const <Null>[],
     });
   }
 }

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

@@ -25,7 +25,7 @@ class PathProvider {
     Map<String, dynamic> result =
       await PlatformMessages.sendJSON('flutter/platform', <String, dynamic>{
         'method': 'PathProvider.getTemporaryDirectory',
-        'args': <Null>[],
+        'args': const <Null>[],
       });
     if (result == null)
       return null;
@@ -44,7 +44,7 @@ class PathProvider {
     Map<String, dynamic> result =
         await PlatformMessages.sendJSON('flutter/platform', <String, dynamic>{
       'method': 'PathProvider.getApplicationDocumentsDirectory',
-      'args': <Null>[],
+      'args': const <Null>[],
     });
     if (result == null)
       return null;

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

+// Copyright 2016 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 'dart:async';
+
+import 'platform_messages.dart';
+
+/// Controls specific aspects of the system navigation stack.
+class SystemNavigator {
+  SystemNavigator._();
+
+  /// Instructs the system navigator to remove this activity from the stack and
+  /// return to the previous activity.
+  ///
+  /// Platform Specific Notes:
+  ///
+  ///   On iOS, this is a no-op because Apple's human interface guidelines state
+  ///   that applications should not exit themselves.
+  static Future<Null> pop() async {
+    await PlatformMessages.sendJSON('flutter/platform', <String, dynamic>{
+      'method': 'SystemNavigator.pop',
+      'args': const <Null>[],
+    });
+  }
+}

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

@@ -164,7 +164,7 @@ abstract class WidgetsBinding extends BindingBase implements GestureBinding, Ren
       if (observer.didPopRoute())
         return;
     }
-    activity.finishCurrentActivity();
+    SystemNavigator.pop();
   }
 
   /// Called when the application lifecycle state changes.

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

@@ -28,7 +28,12 @@ class Title extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    updateTaskDescription(label: title, color: color);
+    SystemChrome.setApplicationSwitcherDescription(
+      new ApplicationSwitcherDescription(
+        label: title,
+        primaryColor: color.value,
+      )
+    );
     return child;
   }