[cros] Remove redundant PNG enconding in UserImage.

chrome/browser/ui/webui/options2/chromeos/user_image_source.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 CHROME_BROWSER_UI_WEBUI_OPTIONS2_CHROMEOS_USER_IMAGE_SOURCE_H_
 #define CHROME_BROWSER_UI_WEBUI_OPTIONS2_CHROMEOS_USER_IMAGE_SOURCE_H_
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "chrome/browser/ui/webui/chrome_url_data_manager.h"
+#include "ui/base/layout.h"
+
+namespace base {
+class RefCountedMemory;
+}
 
 namespace chromeos {
 namespace options2 {
 
 // UserImageSource is the data source that serves user images for users that
 // have it.
 class UserImageSource : public ChromeURLDataManager::DataSource {
  public:
   UserImageSource();
 
   // Called when the network layer has requested a resource underneath
   // the path we registered.
   virtual void StartDataRequest(const std::string& path,
                                 bool is_incognito,
                                 int request_id) OVERRIDE;
 
   virtual std::string GetMimeType(const std::string& path) const OVERRIDE;
 
   // Returns PNG or GIF (when possible and if |is_image_animated| flag
   // is true) encoded image for user with specified email.  If there's
-  // no user with such email, returns the default image.
-  std::vector<unsigned char> GetUserImage(const std::string& email,
-                                          bool is_image_animated) const;
+  // no user with such email, returns the first default image.
+  base::RefCountedMemory* GetUserImage(const std::string& email,
+                                       bool is_image_animated,
+                                       ui::ScaleFactor scale_factor) const;
 
  private:
   virtual ~UserImageSource();
 
   DISALLOW_COPY_AND_ASSIGN(UserImageSource);
 };
 
 }  // namespace options2
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_UI_WEBUI_OPTIONS2_CHROMEOS_USER_IMAGE_SOURCE_H_