Refactor cc scrollbar layers to separate solid-color vs desktop.

content/renderer/gpu/render_widget_compositor.cc

 // Copyright (c) 2013 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/renderer/gpu/render_widget_compositor.h"
 
 #include <limits>
 #include <string>
 
 #include "base/command_line.h"
@@ skipping 263 matching lines @@
           : SkColorSetARGB(128, 128, 128, 128);
   settings.solid_color_scrollbar_thickness_dip = 3;
   settings.highp_threshold_min = 2048;
   // Android WebView handles root layer flings itself.
   settings.ignore_root_layer_flings =
       widget->UsingSynchronousRendererCompositor();
 #elif !defined(OS_MACOSX)
   if (cmd->HasSwitch(switches::kEnableOverlayScrollbars)) {
     settings.scrollbar_animator = cc::LayerTreeSettings::LinearFade;
     settings.solid_color_scrollbars = true;
+  }
+  if (cmd->HasSwitch(cc::switches::kEnablePinchVirtualViewport) ||
+      cmd->HasSwitch(switches::kEnableOverlayScrollbars)) {
     settings.solid_color_scrollbar_color = SkColorSetARGB(128, 128, 128, 128);
     settings.solid_color_scrollbar_thickness_dip = 7;
   }
 #endif
 
   if (!compositor->initialize(settings))
     return scoped_ptr<RenderWidgetCompositor>();
 
   return compositor.Pass();
 }
@@ skipping 293 matching lines @@
   return RenderThreadImpl::current()->OffscreenContextProviderForMainThread();
 }
 
 scoped_refptr<cc::ContextProvider>
 RenderWidgetCompositor::OffscreenContextProviderForCompositorThread() {
   return RenderThreadImpl::current()->
       OffscreenContextProviderForCompositorThread();
 }
 
 }  // namespace content