Implement ChildThread::shutdown and clear members that have refs into blink

content/renderer/render_thread_impl.cc

 // Copyright (c) 2012 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.
 
 #include "content/renderer/render_thread_impl.h"
 
 #include <algorithm>
 #include <limits>
 #include <map>
 #include <vector>
@@ skipping 415 matching lines @@
   TRACE_EVENT_END_ETW("RenderThreadImpl::Init", 0, "");
 }
 
 RenderThreadImpl::~RenderThreadImpl() {
 }
 
 void RenderThreadImpl::Shutdown() {
   FOR_EACH_OBSERVER(
       RenderProcessObserver, observers_, OnRenderProcessShutdown());
 
+  ChildThread::Shutdown();
+
   // Wait for all databases to be closed.
   if (web_database_observer_impl_)
     web_database_observer_impl_->WaitForAllDatabasesToClose();
 
   // Shutdown in reverse of the initialization order.
   if (devtools_agent_message_filter_.get()) {
     RemoveFilter(devtools_agent_message_filter_.get());
     devtools_agent_message_filter_ = NULL;
   }
 
@@ skipping 859 matching lines @@
 
 void RenderThreadImpl::SetFlingCurveParameters(
     const std::vector<float>& new_touchpad,
     const std::vector<float>& new_touchscreen) {
   webkit_platform_support_->SetFlingCurveParameters(new_touchpad,
                                                     new_touchscreen);
 
 }
 
 }  // namespace content