ui + mus: Split ContextFactory into ContextFactory(Client) and ContextFactoryPrivate

content/browser/context_factory.cc

 // Copyright 2014 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 "content/public/browser/context_factory.h"
 
 #include "content/browser/compositor/image_transport_factory.h"
 
 namespace content {
 
 ui::ContextFactory* GetContextFactory() {
   DCHECK(ImageTransportFactory::GetInstance());
   return ImageTransportFactory::GetInstance()->GetContextFactory();
 }
 
+ui::ContextFactoryPrivate* GetContextFactoryPrivate() {
+  DCHECK(ImageTransportFactory::GetInstance());
+  return ImageTransportFactory::GetInstance()->GetContextFactoryPrivate();
+}
+
 }  // namespace content