Track when fallback icon color is the default.

components/favicon_base/fallback_icon_url_parser.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_base/fallback_icon_url_parser.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/macros.h"
@@ skipping 67 matching lines @@
       specs_str, ",", base::KEEP_WHITESPACE, base::SPLIT_WANT_ALL);
   if (tokens.size() != 5)  // Force "," for empty fields.
     return false;
 
   *size = gfx::kFaviconSize;
   if (!tokens[0].empty() && !base::StringToInt(tokens[0], size))
     return false;
   if (*size <= 0)
     return false;
 
-  if (!tokens[1].empty() && !ParseColor(tokens[1], &style->background_color))
-    return false;
+  *style = favicon_base::FallbackIconStyle();
+
+  if (!tokens[1].empty()) {
+    style->is_default_background_color = false;
+    if (!ParseColor(tokens[1], &style->background_color))
+      return false;
+  }
 
   if (tokens[2].empty())
     favicon_base::MatchFallbackIconTextColorAgainstBackgroundColor(style);
   else if (!ParseColor(tokens[2], &style->text_color))
     return false;
 
   if (!tokens[3].empty() &&
       !base::StringToDouble(tokens[3], &style->font_size_ratio))
     return false;
 
@@ skipping 28 matching lines @@
   SkColor temp_color = SK_ColorWHITE;
   const char* end = SkParse::FindColor(color_str.c_str(), &temp_color);
   if (end && !*end) {  // Successful if call succeeds and string is consumed.
     *color = temp_color;
     return true;
   }
   return false;
 }
 
 }  // namespace chrome