Add support for transparent/translucent pixels in the user image

components/user_manager/user.h

 // Copyright 2014 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 COMPONENTS_USER_MANAGER_USER_H_
 #define COMPONENTS_USER_MANAGER_USER_H_
 
 #include <memory>
 #include <string>
 #include <vector>
@@ skipping 120 matching lines @@
 
   // Whether the user has a default image.
   bool HasDefaultImage() const;
 
   int image_index() const { return image_index_; }
   bool has_image_bytes() const { return user_image_->has_image_bytes(); }
   // Returns bytes representation of static user image for WebUI.
   scoped_refptr<base::RefCountedBytes> image_bytes() const {
     return user_image_->image_bytes();
   }
+  // Returns image format of the bytes representation of static user image
+  // for WebUI.
+  UserImage::ImageFormat image_format() const {
+    return user_image_->image_format();
+  }
 
   // Whether |user_image_| contains data in format that is considered safe to
   // decode in sensitive environment (on Login screen).
   bool image_is_safe_format() const { return user_image_->is_safe_format(); }
 
   // Returns the URL of user image, if there is any. Currently only the profile
   // image has a URL, for other images empty URL is returned.
   GURL image_url() const { return user_image_->url(); }
 
   // True if user image is a stub (while real image is being loaded from file).
@@ skipping 151 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(User);
 };
 
 // List of known users.
 using UserList = std::vector<User*>;
 
 }  // namespace user_manager
 
 #endif  // COMPONENTS_USER_MANAGER_USER_H_