mus: Make --use-mus-in-renderer the default for --mash.

content/browser/browser_main_loop.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/browser/browser_main_loop.h"
 
 #include <stddef.h>
 
 #include <string>
 #include <utility>
@@ skipping 1448 matching lines @@
   gpu::GpuChannelEstablishFactory* factory =
       GetContentClient()->browser()->GetGpuChannelEstablishFactory();
   if (!factory) {
     BrowserGpuChannelHostFactory::Initialize(established_gpu_channel);
     factory = BrowserGpuChannelHostFactory::instance();
   }
   DCHECK(factory);
   ImageTransportFactory::Initialize();
   ImageTransportFactory::GetInstance()->SetGpuChannelEstablishFactory(factory);
 #if defined(USE_AURA)
-  bool use_mus_in_renderer = base::CommandLine::ForCurrentProcess()->HasSwitch(
-      switches::kUseMusInRenderer);
-  if (aura::Env::GetInstance() && !use_mus_in_renderer) {
-    aura::Env::GetInstance()->set_context_factory(GetContextFactory());
-    aura::Env::GetInstance()->set_context_factory_private(
-        GetContextFactoryPrivate());
+  bool use_mus_in_renderer = !base::CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kNoUseMusInRenderer);
+  if (env_.get() &&

[sky, 2017/01/31 04:17:30]

env_.get() -> env_.
Also, Env::GetInstance() really be null here?

[sadrul, 2017/01/31 15:45:13]

I don't think so. I have removed this check.

+      (!use_mus_in_renderer || env_->mode() == aura::Env::Mode::LOCAL)) {
+    env_->set_context_factory(GetContextFactory());
+    env_->set_context_factory_private(GetContextFactoryPrivate());
   }
 #endif  // defined(USE_AURA)
 #endif  // defined(OS_ANDROID)
 
   // Enable the GpuMemoryBuffer dump provider with IO thread affinity. Note that
   // unregistration happens on the IO thread (See
   // BrowserProcessSubThread::IOThreadPreCleanUp).
   base::trace_event::MemoryDumpManager::GetInstance()->RegisterDumpProvider(
       BrowserGpuMemoryBufferManager::current(), "BrowserGpuMemoryBufferManager",
       io_thread_->task_runner());
@@ skipping 305 matching lines @@
   if (!audio_manager_) {
     audio_thread_ = base::MakeUnique<AudioManagerThread>();
     audio_manager_ = media::AudioManager::Create(
         audio_thread_->task_runner(), audio_thread_->worker_task_runner(),
         MediaInternals::GetInstance());
   }
   CHECK(audio_manager_);
 }
 
 }  // namespace content