Refactoring: de-couple Extensions from "script injection System" [render side] : 1

extensions/common/extension_messages.h

 // Copyright 2014 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 117 matching lines @@
   // When to inject the code.
   IPC_STRUCT_MEMBER(int, run_at)
 
   // Whether to execute code in the main world (as opposed to an isolated
   // world).
   IPC_STRUCT_MEMBER(bool, in_main_world)
 
   // Whether the request is coming from a <webview>.
   IPC_STRUCT_MEMBER(bool, is_web_view)
 
+  // The script injection instance id of a <webview> if the request is comming
+  // from a <webview>; else, the default instance id (0).
+  IPC_STRUCT_MEMBER(int, instance_id)
+
   // Whether the caller is interested in the result value. Manifest-declared
   // content scripts and executeScript() calls without a response callback
   // are examples of when this will be false.
   IPC_STRUCT_MEMBER(bool, wants_result)
 
   // The URL of the file that was injected, if any.
   IPC_STRUCT_MEMBER(GURL, file_url)
 
   // Whether the code to be executed should be associated with a user gesture.
   IPC_STRUCT_MEMBER(bool, user_gesture)
@@ skipping 632 matching lines @@
                     int /* acc_obj_id */,
                     base::string16 /* selector */)
 
 // Result of a query selector request.
 // result_acc_obj_id is the accessibility tree ID of the result element; 0
 // indicates no result.
 IPC_MESSAGE_ROUTED3(ExtensionHostMsg_AutomationQuerySelector_Result,
                     int /* request_id */,
                     ExtensionHostMsg_AutomationQuerySelector_Error /* error */,
                     int /* result_acc_obj_id */)