Refactor ViewsDelegate singleton

ui/views/cocoa/bridged_native_widget.mm

 // 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.
 
 #import "ui/views/cocoa/bridged_native_widget.h"
 
 #import <objc/runtime.h>
 
 #include "base/logging.h"
 #include "base/mac/mac_util.h"
@@ skipping 759 matching lines @@
 }
 
 gfx::Size BridgedNativeWidget::GetClientAreaSize() const {
   NSRect content_rect = [window_ contentRectForFrameRect:[window_ frame]];
   return gfx::Size(NSWidth(content_rect), NSHeight(content_rect));
 }
 
 void BridgedNativeWidget::CreateCompositor() {
   DCHECK(!compositor_);
   DCHECK(!compositor_widget_);
-  DCHECK(ViewsDelegate::views_delegate);
+  DCHECK(ViewsDelegate::GetInstance());
 
   ui::ContextFactory* context_factory =
-      ViewsDelegate::views_delegate->GetContextFactory();
+      ViewsDelegate::GetInstance()->GetContextFactory();
   DCHECK(context_factory);
 
   AddCompositorSuperview();
 
   // TODO(tapted): Get this value from GpuDataManagerImpl via ViewsDelegate.
   bool needs_gl_finish_workaround = false;
 
   compositor_widget_.reset(
       new ui::AcceleratedWidgetMac(needs_gl_finish_workaround));
   compositor_.reset(new ui::Compositor(compositor_widget_->accelerated_widget(),
@@ skipping 70 matching lines @@
       window_, &kWindowPropertiesKey);
   if (!properties) {
     properties = [NSMutableDictionary dictionary];
     objc_setAssociatedObject(window_, &kWindowPropertiesKey,
                              properties, OBJC_ASSOCIATION_RETAIN);
   }
   return properties;
 }
 
 }  // namespace views