[Icons NTP] Working prototype to fetch, store, and display big icons.

chrome/browser/ui/webui/fallback_icon_source.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 "chrome/browser/ui/webui/fallback_icon_source.h"
 
 #include <string>
 #include <vector>
 
 #include "base/memory/ref_counted_memory.h"
 #include "chrome/browser/search/instant_io_context.h"
 #include "chrome/common/favicon/fallback_icon_url_parser.h"
 #include "chrome/common/url_constants.h"
 #include "grit/platform_locale_settings.h"
 #include "net/url_request/url_request.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/favicon_size.h"
+#include "url/gurl.h"
 
 FallbackIconSource::FallbackIconSource() {
   std::vector<std::string> font_list;
 #if defined(OS_CHROMEOS)
   font_list.push_back("Noto Sans");
 #elif defined(OS_IOS)
   font_list.push_back("Helvetica Neue");
 #else
   font_list.push_back(l10n_util::GetStringUTF8(IDS_SANS_SERIF_FONT_FAMILY));
 #endif
@@ skipping 12 matching lines @@
     const std::string& path,
     int render_process_id,
     int render_frame_id,
     const content::URLDataSource::GotDataCallback& callback) {
   chrome::ParsedFallbackIconPath parsed;
   bool success = parsed.Parse(path);
   if (!success) {
     SendDefaultResponse(callback);
     return;
   }
-
-  GURL url(parsed.url());
+  GURL url(parsed.url_string());
+  if (url.is_empty() || !url.is_valid()) {
+    SendDefaultResponse(callback);
+    return;
+  }
   std::vector<unsigned char> bitmap_data =
       fallback_icon_service_->RenderFallbackIconBitmap(
           url, parsed.size_in_pixels(), parsed.style());
   callback.Run(base::RefCountedBytes::TakeVector(&bitmap_data));
 }
 
 std::string FallbackIconSource::GetMimeType(const std::string&) const {
   // We need to explicitly return a mime type, otherwise if the user tries to
   // drag the image they get no extension.
   return "image/png";
@@ skipping 12 matching lines @@
   return URLDataSource::ShouldServiceRequest(request);
 }
 
 void FallbackIconSource::SendDefaultResponse(
     const content::URLDataSource::GotDataCallback& callback) {
   std::vector<unsigned char> bitmap_data =
       fallback_icon_service_->RenderFallbackIconBitmap(
           GURL(), gfx::kFaviconSize, favicon_base::FallbackIconStyle());
   callback.Run(base::RefCountedBytes::TakeVector(&bitmap_data));
 }