Add more options to --screen-config flag.

ui/display/test/display_matchers.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_TEST_DISPLAY_MATCHERS_H_
+#define UI_DISPLAY_TEST_DISPLAY_MATCHERS_H_
+
+#include "testing/gmock/include/gmock/gmock.h"
+#include "ui/display/types/display_mode.h"
+
+namespace display {
+
+// Matcher for DisplayMode size and refresh rate.
+testing::Matcher<const ui::DisplayMode&>
+IsDisplayMode(int width, int height, float refresh_rate = 60.0f);
+
+}  // namespace display
+
+#endif  // UI_DISPLAY_TEST_DISPLAY_MATCHERS_H_