mus: Introduce high-contrast mode in mus.

services/ui/ws/accessibility_manager.cc

+// 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.
+
+#include "services/ui/ws/accessibility_manager.h"
+
+#include "services/ui/ws/window_server.h"
+
+namespace ui {
+namespace ws {
+
+AccessibilityManager::AccessibilityManager(WindowServer* window_server)
+    : window_server_(window_server), binding_(this) {
+  DCHECK(window_server_);
+}
+
+AccessibilityManager::~AccessibilityManager() {}
+
+void AccessibilityManager::Bind(mojom::AccessibilityManagerRequest request) {
+  if (binding_.is_bound())

[sky, 2016/07/08 16:45:00]

nit: I'm pretty sure you can always call binding_.Close(). It use to be the case
you couldn't, but I believe 618488 fixed it.

[sadrul, 2016/07/08 17:33:25]

Done.

+    binding_.Close();
+  binding_.Bind(std::move(request));
+  binding_.set_connection_error_handler(
+      base::Bind(&mojo::Binding<mojom::AccessibilityManager>::Close,

[sky, 2016/07/08 16:45:00]

Do you really need this? Seems like it doesn't matter if there is a connection
error.

[sadrul, 2016/07/08 17:33:25]

Cool. Removed.

+                 base::Unretained(&binding_)));
+}
+
+void AccessibilityManager::SetHighContrastMode(bool enabled) {
+  window_server_->SetHighContrastMode(enabled);

[sky, 2016/07/08 16:45:00]

Isn't high contrast mode specific to a user and not all users?

[sadrul, 2016/07/08 17:33:25]

Oh yeah, good point. Fixed.

+}
+
+}  // namespace ws
+}  // namespace ui