Create AudioRendererHost in BrowserRenderProcessHost and hook with ResourceMessageFilter

chrome/browser/renderer_host/audio_renderer_host_unittest.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 "base/message_loop.h"
 #include "base/process.h"
 #include "base/scoped_ptr.h"
 #include "chrome/browser/renderer_host/audio_renderer_host.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 class AudioRendererHostTest : public testing::Test {
  protected:
   virtual void SetUp() {
-    host_.reset(new AudioRendererHost(MessageLoop::current()));
+    // Create a message loop so AudioRendererHost can use it.
+    message_loop_.reset(new MessageLoop(MessageLoop::TYPE_IO));
+    host_ = new AudioRendererHost(MessageLoop::current());
   }
 
-  scoped_ptr<AudioRendererHost> host_;
+  virtual void TearDown() {
+    host_->Destroy();
+  }
+
+  scoped_refptr<AudioRendererHost> host_;
+  scoped_ptr<MessageLoop> message_loop_;
 };
 
 TEST_F(AudioRendererHostTest, NoTest) {
   // TODO(hclam): come up with useful tests.
 }