Make BrowserMessageFilter not derive from IPC::ChannelProxy::MessageFilter. This allows us to hide …

content/browser/browser_child_process_host_impl.h

Index: content/browser/browser_child_process_host_impl.h
===================================================================
--- content/browser/browser_child_process_host_impl.h	(revision 225900)
+++ content/browser/browser_child_process_host_impl.h	(working copy)
@@ -21,6 +21,7 @@
 
 class BrowserChildProcessHostIterator;
 class BrowserChildProcessObserver;
+class BrowserMessageFilter;
 
 // Plugins/workers and other child processes that live on the IO thread use this
 // class. RenderProcessHostImpl is the main exception that doesn't use this
@@ -70,6 +71,9 @@
   // shutdown. Default is to always terminate.
   void SetTerminateChildOnShutdown(bool terminate_on_shutdown);
 
+  // Adds an IPC message filter.
+  void AddFilter(BrowserMessageFilter* filter);
+
   // Called when an instance of a particular child is created in a page.
   static void NotifyProcessInstanceCreated(const ChildProcessData& data);