arc: Support more types of notifications.

components/arc/common/bitmap.mojom

Index: components/arc/common/bitmap.mojom
diff --git a/chrome/test/data/extensions/api_test/service_worker/background/post_message_to_sw.js b/components/arc/common/bitmap.mojom
similarity index 60%
copy from chrome/test/data/extensions/api_test/service_worker/background/post_message_to_sw.js
copy to components/arc/common/bitmap.mojom
index be9ae08c6fd493a13f15b480a483529f122d1872..228e995efe274fe8c89f9dae54351aaf92422ac2 100644
--- a/chrome/test/data/extensions/api_test/service_worker/background/post_message_to_sw.js
+++ b/components/arc/common/bitmap.mojom
@@ -2,8 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-'use strict';
+module arc;
 
-self.onmessage = function(e) {
-  e.data.port.postMessage(e.data.message);
+struct ArcBitmap {
+  uint32 width;
+  uint32 height;
+  array<uint8> pixel_data;  // Must be ARGB_8888
 };