arc: Support UNINSTALL_SHORTCUT

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 c255ea8554471c7f4207d81a84abfdf2eaec8e1d..5a0b32ab18e53ae7a5e112928592a628c3b8f19e 100644
--- a/components/arc/common/app.mojom
+++ b/components/arc/common/app.mojom
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
-// Next MinVersion: 18
+// Next MinVersion: 19
 
 module arc.mojom;
 
@@ -75,7 +75,7 @@ enum ShowPackageInfoPage {
   MANAGE_LINKS = 1,
 };
 
-// Next method ID: 16
+// Next method ID: 17
 interface AppHost {
   // 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.
@@ -148,6 +148,11 @@ interface AppHost {
   // Notifies that task requested orientation lock.
   [MinVersion=12] OnTaskOrientationLockRequested@12(int32 task_id,
                                                     OrientationLock lock);
+
+  // Notifies that an application shortcut needs to be deleted. Shortcut is
+  // defined by it's |intent_uri| and |package_name|.

[Luis Héctor Chávez, 2017/05/02 19:48:17]

nit: s/it's/its/.

Also, is it possible to use the ShortcutInfo struct here too, for consistency?

[khmel, 2017/05/02 20:09:43]

Renamed. I tried to use ShortcutInfo in my first impl. However it failed to
serialize ShortcutInfo because this structure contains non-null label  and
icon_resource_id. Of cause it possible for uninstall to pass "" for label and
icon_resource_id but this looks like a hack. Also it is possible to mark them as
nullable in mojo but after this we have to add additional check for
onInstallShortcut. 
Counting that and fact that half of fields is not required I decided to pass
package and intent directly.

[Luis Héctor Chávez, 2017/05/02 20:23:49]

Ah that is very unfortunate :/ All right, seems reasonable.

+  [MinVersion=18] OnUninstallShortcut@16(string package_name,
+                                         string intent_uri);
 };
 
 // TODO(lhchavez): Migrate all request/response messages to Mojo.