Adds AshTest

ash/mus/test/ash_test_impl_mus.h

Index: ash/mus/test/ash_test_impl_mus.h
diff --git a/ash/mus/test/ash_test_impl_mus.h b/ash/mus/test/ash_test_impl_mus.h
new file mode 100644
index 0000000000000000000000000000000000000000..7aa29446efaa403da814de282ef601153dd142cc
--- /dev/null
+++ b/ash/mus/test/ash_test_impl_mus.h
@@ -0,0 +1,48 @@
+// Copyright 2016 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.
+
+#ifndef ASH_MUS_TEST_ASH_TEST_IMPL_MUS_H_
+#define ASH_MUS_TEST_ASH_TEST_IMPL_MUS_H_
+
+#include "ash/common/test/ash_test_impl.h"
+#include "ash/mus/test/wm_test_base.h"
+#include "base/macros.h"
+
+namespace ash {
+namespace mus {
+
+class WmTestBase;
+
+// Implementation of AshTestImpl for mus.
+class AshTestImplMus : public AshTestImpl {
+ public:
+  AshTestImplMus();
+  ~AshTestImplMus() override;
+
+  // AshTestImpl:
+  void SetUp() override;
+  void TearDown() override;
+  bool SupportsMultipleDisplays() const override;
+  void UpdateDisplay(const std::string& display_spec) override;
+  std::unique_ptr<WindowOwner> CreateTestWindow(
+      const gfx::Rect& bounds_in_screen,
+      ui::wm::WindowType type,
+      int shell_window_id) override;
+  display::Display GetSecondaryDisplay() override;
+  bool SetSecondaryDisplayPlacement(
+      display::DisplayPlacement::Position position,
+      int offset) override;
+
+ private:
+  // TODO(sky): fold WmTestBase directly into this class when no more subclasses
+  // of WmTestBase.
+  std::unique_ptr<WmTestBase> wm_test_base_;
+
+  DISALLOW_COPY_AND_ASSIGN(AshTestImplMus);
+};
+
+}  // namespace mus
+}  // namespace ash
+
+#endif  // ASH_MUS_TEST_ASH_TEST_IMPL_MUS_H_