Browser Plugin: Add HTML5-like postMessage support

content/browser/browser_plugin/browser_plugin_embedder.h

Index: content/browser/browser_plugin/browser_plugin_embedder.h
diff --git a/content/browser/browser_plugin/browser_plugin_embedder.h b/content/browser/browser_plugin/browser_plugin_embedder.h
index f47e84904eca36a4e70955938a7b7e595cff953c..712fc3a04a218ff4b98d0008ac65138d1d903b8e 100644
--- a/content/browser/browser_plugin/browser_plugin_embedder.h
+++ b/content/browser/browser_plugin/browser_plugin_embedder.h
@@ -40,6 +40,7 @@ class Size;
 
 class WebContentsImpl;
 
+struct BrowserPluginHostMsg_PostMessage_Params;
 struct BrowserPluginHostMsg_ResizeGuest_Params;
 struct ViewHostMsg_UpdateRect_Params;
 
@@ -135,6 +136,10 @@ class CONTENT_EXPORT BrowserPluginEmbedder : public WebContentsObserver,
                         const WebKit::WebInputEvent& event,
                         IPC::Message* reply_message);
   void PluginDestroyed(int instance_id);
+  // Called when the embedder posts a message to the guest.
+  void RouteMessageEvent(int instance_id,
+                         const string16& data,
+                         const string16& target_origin);
 
   // Called when visiblity of web_contents changes, so the embedder will
   // show/hide its guest.