aura: Allow specifying the size of TestScreen when creating it.

ui/aura/test/test_screen.h

 // Copyright (c) 2012 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_AURA_TEST_TEST_SCREEN_H_
 #define UI_AURA_TEST_TEST_SCREEN_H_
 
 #include "base/compiler_specific.h"
 #include "ui/aura/window_observer.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/screen.h"
 
 namespace gfx {
 class Rect;
 class Transform;
 }
 
 namespace aura {
 class Window;
 class WindowTreeHost;
 
 // A minimal, testing Aura implementation of gfx::Screen.
 class TestScreen : public gfx::Screen,
                    public WindowObserver {
  public:
-  static TestScreen* Create();
+  // Creates a gfx::Screen of the specified size. If no size is specified, then
+  // creates a 800x600 screen. |size| is in physical pixels.
+  static TestScreen* Create(const gfx::Size& size);
   // Creates a TestScreen that uses fullscreen for the display.
   static TestScreen* CreateFullscreen();
   virtual ~TestScreen();
 
   WindowTreeHost* CreateHostForPrimaryDisplay();
 
   void SetDeviceScaleFactor(float device_scale_fator);
   void SetDisplayRotation(gfx::Display::Rotation rotation);
   void SetUIScale(float ui_scale);
 
@@ skipping 33 matching lines @@
   gfx::Display display_;
 
   float ui_scale_;
 
   DISALLOW_COPY_AND_ASSIGN(TestScreen);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_TEST_TEST_SCREEN_H_