Add delay to FakeDisplayDelegate::Configure().

ui/display/fake_display_delegate.h

 // 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 UI_DISPLAY_FAKE_DISPLAY_DELEGATE_H_
 #define UI_DISPLAY_FAKE_DISPLAY_DELEGATE_H_
 
 #include <memory>
 #include <string>
 #include <vector>
 
+#include "base/callback.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
+#include "base/timer/timer.h"
 #include "ui/display/display_export.h"
 #include "ui/display/fake_display_snapshot.h"
 #include "ui/display/types/fake_display_controller.h"
 #include "ui/display/types/native_display_delegate.h"
 
 namespace display {
 
 // A NativeDisplayDelegate implementation that manages fake displays. Fake
 // displays mimic physical displays but do not actually exist. This is because
 // Chrome OS does not take over the entire display when running off device and
@@ skipping 91 matching lines @@
  protected:
   // Sets initial display snapshots from command line flag. Returns true if the
   // spec was parsed successfully.
   bool InitializeFromSpecString(const std::string& str);
 
   // Updates observers when display configuration has changed. Will not update
   // until after |Initialize()| has been called.
   void OnConfigurationChanged();
 
  private:
+  // Performs callback for Configure().
+  void ConfigureDone();
+
   base::ObserverList<ui::NativeDisplayObserver> observers_;
   std::vector<std::unique_ptr<ui::DisplaySnapshot>> displays_;
 
-  // If |Initialize()| has been called.
+  // Add delay before finished Configure().
+  base::OneShotTimer configure_timer_;
+  base::Closure configure_callback_;
+
+  // If Initialize() has been called.
   bool initialized_ = false;
 
   // The next available display id.
   uint8_t next_display_id_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(FakeDisplayDelegate);
 };
 
 }  // namespace display
 #endif  // UI_DISPLAY_FAKE_DISPLAY_DELEGATE_H_