[Local NTP] Fix chrome://large-icon fallback when no favicon is found.

components/favicon/core/large_icon_service.cc

 // Copyright 2015 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.
 
 #include "components/favicon/core/large_icon_service.h"
 
 #include "components/favicon/core/favicon_service.h"
 #include "components/favicon_base/fallback_icon_style.h"
 #include "components/favicon_base/favicon_types.h"
 
@@ skipping 29 matching lines @@
 }
 
 void LargeIconService::RunLargeIconCallback(
     const favicon_base::LargeIconCallback& callback,
     int desired_size_in_pixel,
     const favicon_base::FaviconRawBitmapResult& bitmap_result) {
   // If there are no bitmaps, return a result with an empty |bitmap| and a
   // default |fallback_icon_style|.
   favicon_base::LargeIconResult result;
   if (!bitmap_result.is_valid()) {
+    result.fallback_icon_style.reset(new favicon_base::FallbackIconStyle());

[pkotwicz, 2015/04/27 17:49:02]

Sorry that I missed this. How about adding two new constructors for
LargeIconResult, one which takes a FallbackIconStyle and another which takes in
FaviconRawBitmapResult and removing the default constructor?

[huangs, 2015/04/27 18:16:04]

Done.

     callback.Run(result);
     return;
   }
 
   // If there is a bitmap but it's smaller than the requested size or
   // non-square, compute its dominant color and use it as background in
   // |fallback_icon_style|.
   if (bitmap_result.pixel_size.width() < desired_size_in_pixel ||
       bitmap_result.pixel_size.height() < desired_size_in_pixel ||
       bitmap_result.pixel_size.width() != bitmap_result.pixel_size.height()) {
     // TODO(beaudoin): Resize the icon if it's large enough. Alternatively,
     // return it and let the HTML resize it.
     result.fallback_icon_style.reset(new favicon_base::FallbackIconStyle());
     favicon_base::SetDominantColorAsBackground(
         bitmap_result.bitmap_data, result.fallback_icon_style.get());
     callback.Run(result);
     return;
   }
 
   // The bitmap is square and at least as large as the requested one, return
   // it.
   // TODO(beaudoin): Resize the icon if it's too large. Alternatively, return
   // it and let the HTML resize it.
   result.bitmap = bitmap_result;
   callback.Run(result);
 }
 
 }  // namespace favicon