Faster Reload: Specify AllowCaching = false for some URLDataSources that need it

chrome/browser/ui/webui/fileicon_source.cc

 // Copyright (c) 2012 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/fileicon_source.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted_memory.h"
@@ skipping 128 matching lines @@
   GetFilePathAndQuery(url_path, &file_path, &query);
   ParseQueryParams(query, &scale_factor, &icon_size);
   FetchFileIcon(file_path, scale_factor, icon_size, callback);
 }
 
 std::string FileIconSource::GetMimeType(const std::string&) const {
   // Rely on image decoder inferring the correct type.
   return std::string();
 }
 
+bool FileIconSource::AllowCaching() const {
+  return false;
+}
+
 void FileIconSource::OnFileIconDataAvailable(const IconRequestDetails& details,
                                              gfx::Image* icon) {
   if (icon) {
     scoped_refptr<base::RefCountedBytes> icon_data(new base::RefCountedBytes);
     gfx::PNGCodec::EncodeBGRASkBitmap(
         icon->ToImageSkia()->GetRepresentation(
             details.scale_factor).sk_bitmap(),
         false,
         &icon_data->data());
 
     details.callback.Run(icon_data.get());
   } else {
     // TODO(glen): send a dummy icon.
     details.callback.Run(NULL);
   }
 }