cros: Enable new cras audio handler by default

ash/test/ash_test_helper.cc

 // Copyright 2013 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 "ash/test/ash_test_helper.h"
 
 #include "ash/ash_switches.h"
 #include "ash/shell.h"
 #include "ash/test/display_manager_test_api.h"
 #include "ash/test/shell_test_api.h"
@@ skipping 27 matching lines @@
 AshTestHelper::AshTestHelper(base::MessageLoopForUI* message_loop)
     : message_loop_(message_loop),
       test_shell_delegate_(NULL) {
   CHECK(message_loop_);
 }
 
 AshTestHelper::~AshTestHelper() {
 }
 
 void AshTestHelper::SetUp() {
+  // TODO(jennyz): Create mock or test AudioHandler so we can instantiate
+  // an ash::Shell with the new CrasAudioHandler. crbug.com/233266
+  CommandLine::ForCurrentProcess()->AppendSwitch(
+      ash::switches::kAshDisableNewAudioHandler);
   // TODO(jamescook): Can we do this without changing command line?
   // Use the origin (1,1) so that it doesn't over
   // lap with the native mouse cursor.
   CommandLine::ForCurrentProcess()->AppendSwitchASCII(
       switches::kAshHostWindowBounds, "1+1-800x600");
 #if defined(OS_WIN)
   aura::test::SetUsePopupAsRootWindowForTest(true);
   if (base::win::IsTSFAwareRequired())
     ui::TSFBridge::Initialize();
 #endif
@@ skipping 85 matching lines @@
 aura::RootWindow* AshTestHelper::CurrentContext() {
   aura::RootWindow* root_window = Shell::GetActiveRootWindow();
   if (!root_window)
     root_window = Shell::GetPrimaryRootWindow();
   DCHECK(root_window);
   return root_window;
 }
 
 }  // namespace test
 }  // namespace ash