Allow content script insertion on about:-URLs.

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 98 matching lines @@
 
   // String of code to execute.
   IPC_STRUCT_MEMBER(std::string, code)
 
   // The webview guest source who calls to execute code.
   IPC_STRUCT_MEMBER(GURL, webview_src)
 
   // Whether to inject into all frames, or only the root frame.
   IPC_STRUCT_MEMBER(bool, all_frames)
 
+  // Whether to inject into about:blank (sub)frames.
+  IPC_STRUCT_MEMBER(bool, match_about_blank)
+
   // 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)
 
@@ skipping 503 matching lines @@
 // 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
 //   FrameHostMsg_DidCommitProvisionalLoad. 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 */)