Explicit initialization of aura::Env for browser shell.

ui/aura/test/aura_test_helper.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/test/aura_test_helper.h"
 
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/default_capture_client.h"
@@ skipping 47 matching lines @@
       << "AuraTestHelper::TearDown() never called.";
 }
 
 void AuraTestHelper::SetUp() {
   setup_called_ = true;
 
   // The ContextFactory must exist before any Compositors are created.
   bool allow_test_contexts = true;
   ui::Compositor::InitializeContextFactoryForTests(allow_test_contexts);
 
-  Env::GetInstance();
+  Env::CreateInstance();
   test_screen_.reset(TestScreen::Create());
   gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_NATIVE, test_screen_.get());
   root_window_.reset(test_screen_->CreateRootWindowForPrimaryDisplay());
 
   focus_client_.reset(new FocusManager);
   client::SetFocusClient(root_window_.get(), focus_client_.get());
   stacking_client_.reset(new TestStackingClient(root_window_.get()));
   test_activation_client_.reset(
       new test::TestActivationClient(root_window_.get()));
   capture_client_.reset(new client::DefaultCaptureClient(root_window_.get()));
@@ skipping 27 matching lines @@
 
 void AuraTestHelper::RunAllPendingInMessageLoop() {
   // TODO(jbates) crbug.com/134753 Find quitters of this RunLoop and have them
   //              use run_loop.QuitClosure().
   base::RunLoop run_loop(Env::GetInstance()->GetDispatcher());
   run_loop.RunUntilIdle();
 }
 
 }  // namespace test
 }  // namespace aura