GetScaleFactorForNativeView should return scale factor in float

content/browser/webui/web_ui_impl.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_WEBUI_WEB_UI_IMPL_H_
 #define CONTENT_BROWSER_WEBUI_WEB_UI_IMPL_H_
 
 #include <map>
 #include <set>
 
@@ skipping 16 matching lines @@
 
   // Called by WebContentsImpl when the RenderView is first created. This is
   // *not* called for every page load because in some cases
   // RenderFrameHostManager will reuse RenderView instances.
   void RenderViewCreated(RenderViewHost* render_view_host);
 
   // WebUI implementation:
   virtual WebContents* GetWebContents() const OVERRIDE;
   virtual WebUIController* GetController() const OVERRIDE;
   virtual void SetController(WebUIController* controller) OVERRIDE;
-  virtual ui::ScaleFactor GetDeviceScaleFactor() const OVERRIDE;
+  virtual float GetDeviceScaleFactor() const OVERRIDE;
   virtual const base::string16& GetOverriddenTitle() const OVERRIDE;
   virtual void OverrideTitle(const base::string16& title) OVERRIDE;
   virtual PageTransition GetLinkTransitionType() const OVERRIDE;
   virtual void SetLinkTransitionType(PageTransition type) OVERRIDE;
   virtual int GetBindings() const OVERRIDE;
   virtual void SetBindings(int bindings) OVERRIDE;
   virtual void OverrideJavaScriptFrame(const std::string& frame_name) OVERRIDE;
   virtual void AddMessageHandler(WebUIMessageHandler* handler) OVERRIDE;
   typedef base::Callback<void(const base::ListValue*)> MessageCallback;
   virtual void RegisterMessageCallback(
@@ skipping 66 matching lines @@
   std::string frame_name_;
 
   scoped_ptr<WebUIController> controller_;
 
   DISALLOW_COPY_AND_ASSIGN(WebUIImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_WEBUI_WEB_UI_IMPL_H_