Support uninstalling ARC app from Chrome launcher

components/arc/common/app.mojom

Index: components/arc/common/app.mojom
diff --git a/components/arc/common/app.mojom b/components/arc/common/app.mojom
index b18adbe138643af0212a8b4001fb0c4ebfa7b15f..b799faa4bb07fc410617ff0b7416cc00edb274b7 100644
--- a/components/arc/common/app.mojom
+++ b/components/arc/common/app.mojom
@@ -25,6 +25,7 @@ struct AppInfo {
   string name;
   string package_name;
   string activity;
+  [MinVersion=2] bool uninstallable;
 };
 
 // Represents a rectangle to specify screen coordinates.
@@ -57,6 +58,9 @@ interface AppHost {
   // |icon_png_data| is a png-encoded image.
   OnAppIcon@1(string package_name, string activity,
               ScaleFactor scale_factor, array<uint8> icon_png_data);
+
+  // Sends the error message (null if succeeds) to the host.
+  [MinVersion=2] OnUninstallAppResponse@4(string error_message);
 };
 
 // TODO(lhchavez): Migrate all request/response messages to Mojo.
@@ -85,4 +89,8 @@ interface AppInstance {
   // if it can.
   [MinVersion=1] CanHandleResolution(string package_name, string activity,
                                      ScreenRect dimension) => (bool success);
+
+  // Sends a request to ARC to uninstall the given app.  Response will be
+  // returned via AppHost.OnUninstallAppResponse.
+  [MinVersion=2] UninstallApp(string package);

[Luis Héctor Chávez, 2016/03/04 21:29:37]

Can you instead do

[MinVersion=2] UninstallApp(string package) => (string error_message);

? That is probably going to simplify some stuff.

[khmel, 2016/03/04 22:02:40]

Do we really want sync method? This is UI thread. IMHO we should do async here

[Luis Héctor Chávez, 2016/03/04 22:05:15]

Mojo has no support for sync IPC. This is async :) A second parameter to
UninstallApp() when invoked from C++ will be a
base::Callback<void(mojo::String)>.

[victorhsieh0, 2016/03/07 21:00:16]

Done.

 };