Linux: Refactor X11DesktopHandler

ui/views/widget/desktop_aura/desktop_window_tree_host_x11_interactive_uitest.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 "ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h"
 
 #include <X11/Xlib.h>
 
 #include <memory>
 
@@ skipping 252 matching lines @@
   widget->ShowInactive();
   textfield->RequestFocus();
 
   EXPECT_FALSE(widget->IsActive());
   // TODO(shuchen): uncomment the below check once the
   // "default-focused-input-method" logic is removed in aura::WindowTreeHost.
   //EXPECT_EQ(ui::TEXT_INPUT_TYPE_NONE,
   //          widget->GetInputMethod()->GetTextInputType());
 
   widget->Activate();
+  ActivationWaiter waiter(
+      widget->GetNativeWindow()->GetHost()->GetAcceleratedWidget());
+  waiter.Wait();
 
   EXPECT_TRUE(widget->IsActive());
   EXPECT_EQ(ui::TEXT_INPUT_TYPE_TEXT,
             widget->GetInputMethod()->GetTextInputType());
 
   widget->Deactivate();
 
   EXPECT_FALSE(widget->IsActive());
   EXPECT_EQ(ui::TEXT_INPUT_TYPE_NONE,
             widget->GetInputMethod()->GetTextInputType());
 }
 
 }  // namespace views