Support uninstalling ARC app from Chrome launcher

components/arc/common/app.mojom

 // 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.
+//
+// Next MinVersion: 3
 
 module arc;
 
 // Duplicates ui::ScaleFactor enum in order to be accessible on Android side.
 enum ScaleFactor {
   SCALE_FACTOR_NONE = 0,
   SCALE_FACTOR_100P,
   SCALE_FACTOR_125P,
   SCALE_FACTOR_133P,
   SCALE_FACTOR_140P,
   SCALE_FACTOR_150P,
   SCALE_FACTOR_180P,
   SCALE_FACTOR_200P,
   SCALE_FACTOR_250P,
   SCALE_FACTOR_300P,
 
   NUM_SCALE_FACTORS
 };
 
 // Describes ARC app.
 struct AppInfo {
   string name;
   string package_name;
   string activity;
+  [MinVersion=2] bool sticky;  // true if the app cannot be uninstalled
 };
 
 // Represents a rectangle to specify screen coordinates.
 struct ScreenRect {
   int32 left;
   int32 top;
   int32 right;
   int32 bottom;
 };
 
+// Next method ID: 4
 interface AppHost {
   // Receives a list of available ARC apps to Chrome. Members of AppInfo must
   // contain non-empty string.
   OnAppListRefreshed@0(array<AppInfo> apps);
 
   // Sends newly added ARC app to Chrome. This message is sent when ARC receives
   // package added notification. Multiple apps may be added in the one package.
   [MinVersion=1] OnAppAdded@2(AppInfo app);
 
   // Sends removed ARC package to Chrome. |package_name| must contain non-empty
@@ skipping 12 matching lines @@
 };
 
 // TODO(lhchavez): Migrate all request/response messages to Mojo.
 interface AppInstance {
   Init(AppHost host_ptr);
 
   // Sends a request to ARC to launch an ARC app defined by |package_name| and
   // |activity|, which cannot be empty. |dimension_on_screen| can be null to
   // indicate to use the entire screen.
   LaunchApp(string package_name, string activity,
-            [MinVersion=1] ScreenRect? dimension);
+            [MinVersion=1] ScreenRect? dimension_on_screen);
 
   // Sends a request to ARC to refresh a list of ARC apps.
   // OnRefreshAppsList is expected in response to this message. However,
   // response may not be sent if ARC is not ready yet (boot completed event is
   // not received).
   RefreshAppList();
 
   // Sends a request to ARC for the ARC app icon of a required scale factor.
   // Scale factor is an enum defined at ui/base/layout.h. App is defined by
   // |package_name| and |activity|, which cannot be empty.
   RequestAppIcon(string package_name, string activity,
                  ScaleFactor scale_factor);
 
   // Query if a given resolution can be handled by the application. Returns true
   // if it can.
   [MinVersion=1] CanHandleResolution(string package_name, string activity,
-                                     ScreenRect dimension) => (bool success);
+                                     ScreenRect dimension) => (bool can_handle);
+
+  // Sends a request to ARC to uninstall the given package.  Error (if ever
+  // happens) is ignored, and uninstall option should appear in the UI.
+  [MinVersion=2] UninstallPackage(string package_name);
 };