Split GpuProcessHost into GpuProcessHostUIShim, which runs on the UI...

chrome/browser/child_process_host.cc

 // Copyright (c) 2009 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 "chrome/browser/child_process_host.h"
 
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/file_path.h"
 #include "base/histogram.h"
@@ skipping 62 matching lines @@
       ALLOW_THIS_IN_INITIALIZER_LIST(listener_(this)),
       resource_dispatcher_host_(resource_dispatcher_host),
       opening_channel_(false) {
   Singleton<ChildProcessList>::get()->push_back(this);
 }
 
 
 ChildProcessHost::~ChildProcessHost() {
   Singleton<ChildProcessList>::get()->remove(this);
 
-  resource_dispatcher_host_->CancelRequestsForProcess(id());
+  if (resource_dispatcher_host_)
+    resource_dispatcher_host_->CancelRequestsForProcess(id());
 }
 
 // static
 FilePath ChildProcessHost::GetChildPath(bool allow_self) {
   FilePath child_path;
 
   child_path = CommandLine::ForCurrentProcess()->GetSwitchValuePath(
       switches::kBrowserSubprocessPath);
   if (!child_path.empty())
     return child_path;
@@ skipping 116 matching lines @@
   if (msg.type() == IPC_LOGGING_ID) {
     logger->OnReceivedLoggingMessage(msg);
     return;
   }
 
   if (logger->Enabled())
     logger->OnPreDispatchMessage(msg);
 #endif
 
   bool msg_is_ok = true;
-  bool handled = host_->resource_dispatcher_host_->OnMessageReceived(
-      msg, host_, &msg_is_ok);
+  bool handled = false;
+
+  if (host_->resource_dispatcher_host_)
+    host_->resource_dispatcher_host_->OnMessageReceived(
+        msg, host_, &msg_is_ok);
 
   if (!handled) {
     if (msg.type() == PluginProcessHostMsg_ShutdownRequest::ID) {
       // Must remove the process from the list now, in case it gets used for a
       // new instance before our watcher tells us that the process terminated.
       Singleton<ChildProcessList>::get()->remove(host_);
       if (host_->CanShutdown())
         host_->Send(new PluginProcessMsg_Shutdown());
     } else {
       host_->OnMessageReceived(msg);
@@ skipping 70 matching lines @@
 
     return *iterator_;
   } while (true);
 
   return NULL;
 }
 
 bool ChildProcessHost::Iterator::Done() {
   return iterator_ == Singleton<ChildProcessList>::get()->end();
 }