Extensions: Send the tab id to platform apps.

chrome/common/extensions/extension_messages.h

 // Copyright (c) 2012 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 <string>
 #include <vector>
 
@@ skipping 64 matching lines @@
   // where we expose APIs to normal web pages using the extension function
   // system.
   IPC_STRUCT_MEMBER(std::string, extension_id)
 
   // URL of the frame the request was sent from. This isn't necessarily an
   // extension url. Extension requests can also originate from content scripts,
   // in which case extension_id will indicate the ID of the associated
   // extension. Or, they can originate from hosted apps or normal web pages.
   IPC_STRUCT_MEMBER(GURL, source_url)
 
+  // The id of the tab that sent this request, or -1 if there is no source tab.
+  IPC_STRUCT_MEMBER(int, source_tab_id)
+
   // Unique request id to match requests and responses.
   IPC_STRUCT_MEMBER(int, request_id)
 
   // True if request has a callback specified.
   IPC_STRUCT_MEMBER(bool, has_callback)
 
   // True if request is executed in response to an explicit user gesture.
   IPC_STRUCT_MEMBER(bool, user_gesture)
 IPC_STRUCT_END()
 
@@ skipping 575 matching lines @@
 // Notifies the browser process that a tab has started or stopped matching
 // certain conditions.  This message is sent in response to several events:
 //
 // * ExtensionMsg_WatchPages was received, updating the set of conditions.
 // * A new page is loaded.  This will be sent after ViewHostMsg_FrameNavigate.
 //   Currently this only fires for the main frame.
 // * Something changed on an existing frame causing the set of matching searches
 //   to change.
 IPC_MESSAGE_ROUTED1(ExtensionHostMsg_OnWatchedPageChange,
                     std::vector<std::string> /* Matching CSS selectors */)