Revert of Sets the default background color of inline signin and user manager to grey

content/browser/renderer_host/render_widget_host_view_mac.h

 // Copyright (c) 2012 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 
 #import <Cocoa/Cocoa.h>
 #include <IOSurface/IOSurfaceAPI.h>
 #include <list>
@@ skipping 232 matching lines @@
   virtual void SetShowingContextMenu(bool showing) override;
   virtual void SetActive(bool active) override;
   virtual void SetTakesFocusOnlyOnMouseDown(bool flag) override;
   virtual void SetWindowVisibility(bool visible) override;
   virtual void WindowFrameChanged() override;
   virtual void ShowDefinitionForSelection() override;
   virtual bool SupportsSpeech() const override;
   virtual void SpeakSelection() override;
   virtual bool IsSpeaking() const override;
   virtual void StopSpeaking() override;
-  virtual void SetBackgroundColor(SkColor color) override;
+  virtual void SetBackgroundOpaque(bool opaque) override;
 
   // Implementation of RenderWidgetHostViewBase.
   virtual void InitAsPopup(RenderWidgetHostView* parent_host_view,
                            const gfx::Rect& pos) override;
   virtual void InitAsFullscreen(
       RenderWidgetHostView* reference_host_view) override;
   virtual void WasShown() override;
   virtual void WasHidden() override;
   virtual void MovePluginWindows(
       const std::vector<WebPluginGeometry>& moves) override;
@@ skipping 243 matching lines @@
 
   // The current caret bounds.
   gfx::Rect caret_rect_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewMac);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_