arc: Set custom icon in shelf for ARC apps.

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 5d6045ba2cbe04f4f186e53bdbe08a4a77fe9c68..254d182fb6f1bb1008a2484fcc76b22872b71d90 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: 19
+// Next MinVersion: 20
 
 module arc.mojom;
 
@@ -75,7 +75,7 @@ enum ShowPackageInfoPage {
   MANAGE_LINKS = 1,
 };
 
-// Next method ID: 17
+// Next method ID: 18
 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.
@@ -128,6 +128,11 @@ interface AppHost {
   // Notifies that task has been activated.
   [MinVersion=4] OnTaskSetActive@6(int32 task_id);
 
+  // Sends task description.

[Luis Héctor Chávez, 2017/05/18 18:09:40]

nit: Sends task label and icon.

[khmel, 2017/05/18 20:27:52]

Done.

+  [MinVersion=19] OnTaskSetDescription@17(int32 task_id,
+                                          string label,
+                                          array<uint8> icon_png_data);
+
   // Notifies that notifications enabled settings in Android is changed.
   [MinVersion=7] OnNotificationsEnabledChanged@7(string package_name,
                                                  bool enabled);