gfx::Screen: Replace GetWindowUnderCursor() with IsWindowUnderCursor().

ui/gfx/test/test_screen.h

 // Copyright 2015 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 <vector>
 
 #include "base/macros.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/screen.h"
 
 namespace gfx {
 namespace test {
 
 // A dummy implementation of gfx::Screen that contains a single gfx::Display
 // only. The contained gfx::Display can be accessed and modified via
 // TestScreen::display().
 //
 // NOTE: Adding and removing gfx::DisplayOberver's are no-ops and observers will
 // NOT be notified ever.
 class TestScreen : public gfx::Screen {
  public:
   TestScreen();
   ~TestScreen() override;
 
   gfx::Display* display() { return &display_; }
 
   // gfx::Screen:
   gfx::Point GetCursorScreenPoint() override;
-  gfx::NativeWindow GetWindowUnderCursor() override;
+  bool IsWindowUnderCursor(gfx::NativeWindow window) override;
   gfx::NativeWindow GetWindowAtScreenPoint(const gfx::Point& point) override;
   int GetNumDisplays() const override;
   std::vector<gfx::Display> GetAllDisplays() const override;
   gfx::Display GetDisplayNearestWindow(gfx::NativeView view) const override;
   gfx::Display GetDisplayNearestPoint(const gfx::Point& point) const override;
   gfx::Display GetDisplayMatching(const gfx::Rect& match_rect) const override;
   gfx::Display GetPrimaryDisplay() const override;
   void AddObserver(gfx::DisplayObserver* observer) override;
   void RemoveObserver(gfx::DisplayObserver* observer) override;
 
  private:
   // The only display.
   gfx::Display display_;
 
   DISALLOW_COPY_AND_ASSIGN(TestScreen);
 };
 
 }  // namespace test
 }  // namespace gfx