Add RetainedRef uses where needed.

chrome/browser/media_galleries/fileapi/readahead_file_stream_reader.cc

 // 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.
 
 #include "chrome/browser/media_galleries/fileapi/readahead_file_stream_reader.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 
@@ skipping 87 matching lines @@
 void ReadaheadFileStreamReader::ReadFromSourceIfNeeded() {
   if (!source_.get() || source_has_pending_read_ ||
       buffers_.size() >= kDesiredNumberOfBuffers) {
     return;
   }
 
   source_has_pending_read_ = true;
 
   scoped_refptr<net::IOBuffer> buf(new net::IOBuffer(kBufferSize));
   int result = source_->Read(
-      buf.get(),
-      kBufferSize,
+      buf.get(), kBufferSize,
       base::Bind(&ReadaheadFileStreamReader::OnFinishReadFromSource,
-                 weak_factory_.GetWeakPtr(),
-                 buf));
+                 weak_factory_.GetWeakPtr(), base::RetainedRef(buf)));
 
   if (result != net::ERR_IO_PENDING)
     OnFinishReadFromSource(buf.get(), result);
 }
 
 void ReadaheadFileStreamReader::OnFinishReadFromSource(net::IOBuffer* buf,
                                                        int result) {
   DCHECK(result != net::ERR_IO_PENDING);
   DCHECK(source_has_pending_read_);
   source_has_pending_read_ = false;
@@ skipping 17 matching lines @@
     // Free the pending callback before running it, as the callback often
     // dispatches another read.
     scoped_refptr<net::DrainableIOBuffer> sink = pending_sink_buffer_;
     pending_sink_buffer_ = NULL;
     net::CompletionCallback completion_callback = pending_read_callback_;
     pending_read_callback_.Reset();
 
     completion_callback.Run(FinishReadFromCacheOrStoredError(sink.get()));
   }
 }