Revert of [BlobStorage] Implementing disk.

storage/browser/blob/blob_reader.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 "storage/browser/blob/blob_reader.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
 #include <limits>
 #include <memory>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
-#include "base/debug/stack_trace.h"
 #include "base/sequenced_task_runner.h"
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
 #include "net/disk_cache/disk_cache.h"
 #include "storage/browser/blob/blob_data_handle.h"
 #include "storage/browser/blob/blob_data_snapshot.h"
 #include "storage/browser/fileapi/file_stream_reader.h"
 #include "storage/browser/fileapi/file_system_context.h"
@@ skipping 637 matching lines @@
 void BlobReader::SetFileReaderAtIndex(
     size_t index,
     std::unique_ptr<FileStreamReader> reader) {
   if (reader)
     index_to_reader_[index] = std::move(reader);
   else
     index_to_reader_.erase(index);
 }
 
 }  // namespace storage