Explicit initialization of aura::Env for browser shell.

ui/aura/env.h

Index: ui/aura/env.h
diff --git a/ui/aura/env.h b/ui/aura/env.h
index c52b892d573587226fec4cd678616c09030df500..337e94fd642f6827d0001309904ba1498d00d0e4 100644
--- a/ui/aura/env.h
+++ b/ui/aura/env.h
@@ -22,7 +22,7 @@ class EnvObserver;
 class RootWindow;
 class Window;
 
-#if !defined(USE_X11)
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID) && !defined(USE_X11)
 // Creates a platform-specific native event dispatcher.
 base::MessageLoop::Dispatcher* CreateDispatcher();
 #endif
@@ -34,6 +34,7 @@ class AURA_EXPORT Env : public ui::EventTarget {
   Env();
   virtual ~Env();
 
+  static void CreateInstance();
   static Env* GetInstance();
   static void DeleteInstance();
 
@@ -60,7 +61,10 @@ class AURA_EXPORT Env : public ui::EventTarget {
   // Returns the native event dispatcher. The result should only be passed to
   // base::RunLoop(dispatcher), or used to dispatch an event by
   // |Dispatch(const NativeEvent&)| on it. It must never be stored.
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID) && \
+    !defined(USE_GTK_MESSAGE_PUMP)
   base::MessageLoop::Dispatcher* GetDispatcher();
+#endif
 
   // Invoked by RootWindow when its host is activated.
   void RootWindowActivated(RootWindow* root_window);
@@ -82,7 +86,7 @@ class AURA_EXPORT Env : public ui::EventTarget {
   virtual ui::EventTarget* GetParentTarget() OVERRIDE;
 
   ObserverList<EnvObserver> observers_;
-#if !defined(USE_X11)
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID) && !defined(USE_X11)
   scoped_ptr<base::MessageLoop::Dispatcher> dispatcher_;
 #endif