mash: Convert OnWindowInputEventAck to use an enum for handled status

components/mus/ws/window_tree_unittest.cc

 // Copyright 2014 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 <stdint.h>
 
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
@@ skipping 109 matching lines @@
     DisplayTestApi(display_).OnEvent(event);
   }
 
   void set_window_manager_internal(WindowTree* tree,
                                    mojom::WindowManager* wm_internal) {
     WindowTreeTestApi(tree).set_window_manager_internal(wm_internal);
   }
 
   void AckPreviousEvent() {
     WindowManagerStateTestApi test_api(display_->GetActiveWindowManagerState());
-    while (test_api.tree_awaiting_input_ack())
-      test_api.tree_awaiting_input_ack()->OnWindowInputEventAck(0, true);
+    while (test_api.tree_awaiting_input_ack()) {
+      test_api.tree_awaiting_input_ack()->OnWindowInputEventAck(
+          0, mojom::EventResult::HANDLED);
+    }
   }
 
   void DispatchEventAndAckImmediately(const ui::Event& event) {
     DispatchEventWithoutAck(event);
     AckPreviousEvent();
   }
 
   // Creates a new window from wm_tree() and embeds a new connection in
   // it.
   void SetupEventTargeting(TestWindowTreeClient** out_client,
@@ skipping 728 matching lines @@
   ASSERT_NE(new_opacity, unknown_window.opacity());
 
   EXPECT_FALSE(tree->SetWindowOpacity(
       ClientWindowId(WindowIdToTransportId(window_id)), new_opacity));
   EXPECT_NE(new_opacity, unknown_window.opacity());
 }
 
 }  // namespace test
 }  // namespace ws
 }  // namespace mus