Implement High Contrast mode for Chrome OS

ash/high_contrast/high_contrast_controller.cc

Index: ash/high_contrast/high_contrast_controller.cc
diff --git a/ash/high_contrast/high_contrast_controller.cc b/ash/high_contrast/high_contrast_controller.cc
new file mode 100644
index 0000000000000000000000000000000000000000..cf00d92d734c5e1a8b2318609047bc890985b9d9
--- /dev/null
+++ b/ash/high_contrast/high_contrast_controller.cc
@@ -0,0 +1,26 @@
+// 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 "ash/high_contrast/high_contrast_controller.h"
+
+#include "ash/shell.h"
+#include "ui/aura/root_window.h"
+#include "ui/compositor/layer.h"
+
+namespace ash {
+namespace internal {
+
+HighContrastController::HighContrastController()
+    : enable_(false) {
+  root_window_ = ash::Shell::GetRootWindow();
+}
+
+void HighContrastController::SetEnable(bool enable) {
+  enable_ = enable;
+
+  root_window_->layer()->SetInvert(enable_);
+}
+
+}  // namespace internal
+}  // namespace ash