Adds ability for ash_unittests to run in mushrome mode

ash/test/ash_test_suite.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 "ash/test/ash_test_suite.h"
 
+#include "ash/public/cpp/config.h"
 #include "ash/test/ash_test_environment.h"
+#include "ash/test/ash_test_helper.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/i18n/rtl.h"
 #include "base/path_service.h"
 #include "build/build_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/ui_base_paths.h"
+#include "ui/compositor/test/fake_context_factory.h"
 #include "ui/gfx/gfx_paths.h"
 #include "ui/gl/test/gl_surface_test_support.h"
 
 namespace ash {
 namespace test {
 
 AshTestSuite::AshTestSuite(int argc, char** argv) : TestSuite(argc, argv) {}
 
 AshTestSuite::~AshTestSuite() {}
 
@@ skipping 21 matching lines @@
     ui::ResourceBundle::GetSharedInstance().AddDataPackFromPath(
         ash_test_resources_100, ui::SCALE_FACTOR_100P);
   }
   if (ui::ResourceBundle::IsScaleFactorSupported(ui::SCALE_FACTOR_200P)) {
     base::FilePath ash_test_resources_200 =
         path.Append(FILE_PATH_LITERAL("ash_test_resources_200_percent.pak"));
     ui::ResourceBundle::GetSharedInstance().AddDataPackFromPath(
         ash_test_resources_200, ui::SCALE_FACTOR_200P);
   }
 
+  const bool is_classic =

[msw, 2017/03/30 23:06:05]

optional nit: is_mus would be a one-liner.

[sky, 2017/03/30 23:35:46]

Nice!

+      !base::CommandLine::ForCurrentProcess()->HasSwitch("mus");
+  ash::test::AshTestHelper::config_ =
+      is_classic ? Config::CLASSIC : Config::MUS;
+
   base::DiscardableMemoryAllocator::SetInstance(&discardable_memory_allocator_);
-  env_ = aura::Env::CreateInstance();
+  env_ = aura::Env::CreateInstance(is_classic ? aura::Env::Mode::LOCAL
+                                              : aura::Env::Mode::MUS);
+
+  if (!is_classic) {
+    context_factory_ = base::MakeUnique<ui::FakeContextFactory>();
+    env_->set_context_factory(context_factory_.get());
+    env_->set_context_factory_private(nullptr);
+  }
 }
 
 void AshTestSuite::Shutdown() {
   env_.reset();
   ui::ResourceBundle::CleanupSharedInstance();
   base::TestSuite::Shutdown();
 }
 
 }  // namespace test
 }  // namespace ash