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

content/browser/browser_child_process_host_impl.cc

Index: content/browser/browser_child_process_host_impl.cc
===================================================================
--- content/browser/browser_child_process_host_impl.cc	(revision 225900)
+++ content/browser/browser_child_process_host_impl.cc	(working copy)
@@ -100,9 +100,9 @@
   data_.id = ChildProcessHostImpl::GenerateChildProcessUniqueId();
 
   child_process_host_.reset(ChildProcessHost::Create(this));
-  child_process_host_->AddFilter(new TraceMessageFilter);
-  child_process_host_->AddFilter(new ProfilerMessageFilter(process_type));
-  child_process_host_->AddFilter(new HistogramMessageFilter());
+  AddFilter(new TraceMessageFilter);
+  AddFilter(new ProfilerMessageFilter(process_type));
+  AddFilter(new HistogramMessageFilter);
 
   g_child_process_list.Get().push_back(this);
   GetContentClient()->browser()->BrowserChildProcessHostCreated(this);
@@ -218,6 +218,10 @@
   child_process_->SetTerminateChildOnShutdown(terminate_on_shutdown);
 }
 
+void BrowserChildProcessHostImpl::AddFilter(BrowserMessageFilter* filter) {
+  child_process_host_->AddFilter(filter->GetFilter());
+}
+
 void BrowserChildProcessHostImpl::NotifyProcessInstanceCreated(
     const ChildProcessData& data) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));