Wires up InputDeviceClient for mash/mushrome

ash/test/ash_test_helper.h

Index: ash/test/ash_test_helper.h
diff --git a/ash/test/ash_test_helper.h b/ash/test/ash_test_helper.h
index 9e61a5f389fbf7e35e9c7bb1adc0633657d70a09..a0f7aaf557c92a2a54573270297a9988f8871d8d 100644
--- a/ash/test/ash_test_helper.h
+++ b/ash/test/ash_test_helper.h
@@ -19,7 +19,7 @@
 namespace aura {
 class Window;
 class WindowTreeClientPrivate;
-}  // namespace aura
+}
 
 namespace display {
 class Display;
@@ -33,7 +33,8 @@ class MashTestSuite;
 
 namespace ui {
 class ScopedAnimationDurationScaleMode;
-}  // namespace ui
+class InputDeviceClient;
+}
 
 namespace wm {
 class WMState;
@@ -165,6 +166,8 @@ class AshTestHelper {
 
   std::unique_ptr<TestSessionControllerClient> session_controller_client_;
 
+  std::unique_ptr<ui::InputDeviceClient> input_device_client_;
+
   DISALLOW_COPY_AND_ASSIGN(AshTestHelper);
 };