Make user_manager::UserImage non-copyable

components/user_manager/user_image/user_image.h

Index: components/user_manager/user_image/user_image.h
diff --git a/components/user_manager/user_image/user_image.h b/components/user_manager/user_image/user_image.h
index d6621be66e37eb7b8ae9e4a4100ea956ead2ac62..cf02855a01d4bf93e056bb1d9cc432ca8aeaa304 100644
--- a/components/user_manager/user_image/user_image.h
+++ b/components/user_manager/user_image/user_image.h
@@ -29,9 +29,9 @@ class USER_MANAGER_EXPORT UserImage {
   static scoped_ptr<Bytes> Encode(const SkBitmap& bitmap);
 
   // Creates a new instance from a given still frame and tries to encode it
-  // to bytes representation for WebUI.
+  // to bytes representation for WebUI. Always returns a non-null result.
   // TODO(ivankr): remove eventually.
-  static UserImage CreateAndEncode(const gfx::ImageSkia& image);
+  static scoped_ptr<UserImage> CreateAndEncode(const gfx::ImageSkia& image);
 
   // Create instance with an empty still frame and no bytes
   // representation for WebUI.
@@ -76,6 +76,8 @@ class USER_MANAGER_EXPORT UserImage {
   // If image was loaded from the local file, file path is stored here.
   base::FilePath file_path_;
   bool is_safe_format_;
+
+  DISALLOW_COPY_AND_ASSIGN(UserImage);
 };
 
 }  // namespace user_manager