Relanding: Add js api for hosted/packaged apps to request notification authorization

chrome/common/extensions/extension_messages.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // IPC messages for extensions.
 // Multiply-included message file, hence no include guard.
 
 #include "base/shared_memory.h"
 #include "base/values.h"
 #include "chrome/common/extensions/extension.h"
@@ skipping 306 matching lines @@
                     int32 /* install id */,
                     std::string /* Web Store item ID */,
                     GURL /* requestor URL */)
 
 // Send to renderer once the installation mentioned above is complete.
 IPC_MESSAGE_ROUTED3(ExtensionMsg_InlineWebstoreInstallResponse,
                     int32 /* install id */,
                     bool /* whether the install was successful */,
                     std::string /* error */)
 
+// Sent by the renderer when an App is requesting permission to send server
+// pushed notifications.
+IPC_MESSAGE_ROUTED3(ExtensionHostMsg_GetAppNotifyChannel,
+                    int32 /* request_id */,
+                    GURL /* requestor_url */,
+                    std::string /* client_id */)
+
+// Response to the renderer for the above message.
+IPC_MESSAGE_ROUTED3(ExtensionMsg_GetAppNotifyChannelResponse,
+                    int32 /* request_id */,
+                    std::string /* channel_id */,
+                    std::string /* error */)
+
 // Deliver a message sent with ExtensionHostMsg_PostMessage.
 IPC_MESSAGE_ROUTED2(ExtensionMsg_DeliverMessage,
                     int /* target_port_id */,
                     std::string /* message */)