Don't try to download 'NothingToDownload' placeholder avatar.

chrome/browser/profiles/profile_avatar_icon_util.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 CHROME_BROWSER_PROFILES_PROFILE_AVATAR_ICON_UTIL_H_
 #define CHROME_BROWSER_PROFILES_PROFILE_AVATAR_ICON_UTIL_H_
 
 #include <string>
 
 #include "third_party/skia/include/core/SkColor.h"
@@ skipping 49 matching lines @@
 // so that when resized to a square aspect ratio it looks pretty.
 SkBitmap GetAvatarIconAsSquare(const SkBitmap& source_bitmap, int scale_factor);
 
 // Gets the number of default avatar icons that exist.
 size_t GetDefaultAvatarIconCount();
 
 // Gets the number of generic avatar icons that exist.
 size_t GetGenericAvatarIconCount();
 
 // Gets the index for the (grey silhouette) avatar used as a placeholder.
-int GetPlaceholderAvatarIndex();
+size_t GetPlaceholderAvatarIndex();
 
 // Gets the resource ID of the placeholder avatar icon.
 int GetPlaceholderAvatarIconResourceID();
 
 // Gets the resource ID of the default avatar icon at |index|.
 int GetDefaultAvatarIconResourceIDAtIndex(size_t index);
 
 // Gets the resource filename of the default avatar icon at |index|.
 const char* GetDefaultAvatarIconFileNameAtIndex(size_t index);
 
-// Gets the file name of an avatar that has no high res version.
-const char* GetNoHighResAvatarFileName();
-
 // Gets the full path of the high res avatar icon at |index|.
 base::FilePath GetPathOfHighResAvatarAtIndex(size_t index);
 
 // Returns a URL for the default avatar icon with specified index.
 std::string GetDefaultAvatarIconUrl(size_t index);
 
 // Checks if |index| is a valid avatar icon index
 bool IsDefaultAvatarIconIndex(size_t index);
 
 // Checks if the given URL points to one of the default avatar icons. If it
 // is, returns true and its index through |icon_index|. If not, returns false.
 bool IsDefaultAvatarIconUrl(const std::string& icon_url, size_t *icon_index);
 
 }  // namespace profiles
 
 #endif  // CHROME_BROWSER_PROFILES_PROFILE_AVATAR_ICON_UTIL_H_