Stop chrome from initializing ozone inside mash.

ui/aura/env.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 "ui/aura/env.h"
 
+#include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/threading/thread_local.h"
 #include "ui/aura/env_observer.h"
 #include "ui/aura/input_state_lookup.h"
 #include "ui/events/event_target_iterator.h"
 #include "ui/events/platform/platform_event_source.h"
 
 #if defined(USE_OZONE)
 #include "ui/ozone/public/ozone_platform.h"
 #endif
 
 namespace aura {
 
 namespace {
 
 // Env is thread local so that aura may be used on multiple threads.
 base::LazyInstance<base::ThreadLocalPointer<Env> >::Leaky lazy_tls_ptr =
     LAZY_INSTANCE_INITIALIZER;
 
+#if defined(USE_OZONE)
+// Returns true if running inside of mus. Checks for mojo specific flag.
+bool RunningInsideMus() {
+  return base::CommandLine::ForCurrentProcess()->HasSwitch(
+      "primordial-pipe-token");
+}
+#endif
+
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
 // Env, public:
 
 // static
 void Env::CreateInstance(bool create_event_source) {
   if (!lazy_tls_ptr.Pointer()->Get())
     (new Env())->Init(create_event_source);
 }
@@ skipping 45 matching lines @@
   FOR_EACH_OBSERVER(EnvObserver, observers_, OnWillDestroyEnv());
   DCHECK_EQ(this, lazy_tls_ptr.Pointer()->Get());
   lazy_tls_ptr.Pointer()->Set(NULL);
 }
 
 void Env::Init(bool create_event_source) {
   if (!create_event_source)
     return;
 #if defined(USE_OZONE)
   // The ozone platform can provide its own event source. So initialize the
-  // platform before creating the default event source.
-  ui::OzonePlatform::InitializeForUI();
+  // platform before creating the default event source. If running inside mus
+  // let the mus process initialize ozone instead.
+  if (!RunningInsideMus())
+    ui::OzonePlatform::InitializeForUI();
 #endif
   if (!ui::PlatformEventSource::GetInstance())
     event_source_ = ui::PlatformEventSource::CreateDefault();
 }
 
 void Env::NotifyWindowInitialized(Window* window) {
   FOR_EACH_OBSERVER(EnvObserver, observers_, OnWindowInitialized(window));
 }
 
 void Env::NotifyHostInitialized(WindowTreeHost* host) {
@@ skipping 18 matching lines @@
 scoped_ptr<ui::EventTargetIterator> Env::GetChildIterator() const {
   return nullptr;
 }
 
 ui::EventTargeter* Env::GetEventTargeter() {
   NOTREACHED();
   return NULL;
 }
 
 }  // namespace aura