aura: Allow platform to choose how it retrieves ICCProfile.

ui/views/mus/window_tree_host_mus.cc

 // 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 "ui/views/mus/window_tree_host_mus.h"
 
 #include "base/memory/ptr_util.h"
 #include "services/ui/public/cpp/window.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
@@ skipping 76 matching lines @@
     GetInputMethod()->OnBlur();
   if (native_widget_)
     native_widget_->OnActivationChanged(active);
   WindowTreeHostPlatform::OnActivationChanged(active);
 }
 
 void WindowTreeHostMus::OnCloseRequest() {
   OnHostCloseRequested();
 }
 
+gfx::ICCProfile WindowTreeHostMus::GetICCProfileForCurrentDisplay() {
+  // TODO: This should read the profile from mus. crbug.com/647510
+  return gfx::ICCProfile();
+}
+
 }  // namespace views