Refactor screen/monitor so that gfx::Screen returns monitor object.

ui/gfx/monitor_unittest.cc

+// 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.
+
+#include "ui/gfx/monitor.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/gfx/insets.h"
+
+namespace {
+
+TEST(MonitorTest, WorkArea) {
+  gfx::Monitor monitor(0, gfx::Rect(0, 0, 100, 100));
+  EXPECT_EQ("0,0 100x100", monitor.work_area().ToString());
+
+  monitor.set_work_area(gfx::Rect(3, 4, 90, 80));
+  EXPECT_EQ("3,4 90x80", monitor.work_area().ToString());
+
+  monitor.SetBoundsAndUpdateWorkArea(gfx::Rect(10, 20, 50, 50));
+  EXPECT_EQ("13,24 40x30", monitor.work_area().ToString());
+
+  monitor.SetSizeAndUpdateWorkArea(gfx::Size(200, 200));
+  EXPECT_EQ("13,24 190x180", monitor.work_area().ToString());
+
+  monitor.UpdateWorkAreaWithInsets(gfx::Insets(3, 4, 5, 6));
+  EXPECT_EQ("14,23 190x192", monitor.work_area().ToString());
+}
+
+}