[cros] Added histograms for user image usage

chrome/browser/chromeos/login/user_manager.h

 // Copyright (c) 2011 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_CHROMEOS_LOGIN_USER_MANAGER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USER_MANAGER_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 44 matching lines @@
     std::string GetDisplayName() const;
 
     // Tooltip contains user's display name and his email domain to distinguish
     // this user from the other one with the same display name.
     std::string GetNameTooltip() const;
 
     // Returns true if some users have same display name.
     bool NeedsNameTooltip() const;
 
     // The image for this user.
-    void set_image(const SkBitmap& image) { image_ = image; }
+    void SetImage(const SkBitmap& image,
+                  int default_image_index);
     const SkBitmap& image() const { return image_; }
+    int default_image_index() const { return default_image_index_; }
 
     // OAuth token status for this user.
     OAuthTokenStatus oauth_token_status() const { return oauth_token_status_; }
     void set_oauth_token_status(OAuthTokenStatus status) {
       oauth_token_status_ = status;
     }
 
    private:
     friend class UserManager;
 
     std::string email_;
     SkBitmap image_;
     OAuthTokenStatus oauth_token_status_;
 
     // Cached flag of whether any users has same display name.
     bool is_displayname_unique_;
+
+    // Index of the default image the user has set. -1 if it's some other
+    // image.
+    int default_image_index_;
   };
 
   // Gets a shared instance of a UserManager. Not thread-safe...should
   // only be called from the main UI thread.
   static UserManager* Get();
 
   // Registers user manager preferences.
   static void RegisterPrefs(PrefService* local_state);
 
   // Returns a list of the users who have logged into this device previously.
@@ skipping 130 matching lines @@
   ObserverList<Observer> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(UserManager);
 };
 
 typedef std::vector<UserManager::User> UserVector;
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USER_MANAGER_H_