Add IPC messages for ARC notification

components/arc/arc_bridge_service.h

Index: components/arc/arc_bridge_service.h
diff --git a/components/arc/arc_bridge_service.h b/components/arc/arc_bridge_service.h
index 78e8fa8d2bfbdcd08b6c745895975e0a0ac3a3d7..2d65f5fb4c02c285050ca72807896e6de8d500b6 100644
--- a/components/arc/arc_bridge_service.h
+++ b/components/arc/arc_bridge_service.h
@@ -10,6 +10,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "components/arc/common/arc_message_types.h"
+#include "components/arc/common/arc_notification_types.h"
 
 namespace base {
 class CommandLine;
@@ -75,6 +76,13 @@ class ArcBridgeService {
     // Called whenever ARC's availability has changed for this system.
     virtual void OnAvailableChanged(bool available) {}
 
+    // Called whenever a notification has been posted on Android side. This
+    // event is used for both creation and update.
+    virtual void OnNotificationPostedFromAndroid(

[khmel1, 2015/12/01 06:44:51]

Please pay attention that I added AppsObserver in my CL (still under review).
Probably it makes sens to add NotifyObserver. Having one huge observer might be
inconvenient and have performance implication.

[yoshiki, 2015/12/02 02:38:24]

Done. I added NotificationObserver.

+        const ArcNotificationData& data) {}
+    // Called whenever a notification has been removed on Android side.
+    virtual void OnNotificationRemovedFromAndroid(const std::string& key) {}
+
    protected:
     virtual ~Observer() {}
   };
@@ -129,6 +137,10 @@ class ArcBridgeService {
                                    const std::string& device_type,
                                    base::ScopedFD fd) = 0;
 
+  // Notifies a notification event to Android side.

[hidehiko, 2015/12/01 06:35:43]

nit: s/Notifies/Sends/

[yoshiki, 2015/12/02 02:38:24]

Done.

+  virtual bool SendNotificationEventToAndroid(const std::string& key,
+                                              ArcNotificationEvent event) = 0;
+
  protected:
   ArcBridgeService();