Update from https://crrev.com/306655

net/quic/quic_stream_sequencer.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 "net/quic/quic_stream_sequencer.h"
 
 #include <algorithm>
 #include <limits>
 
 #include "base/logging.h"
@@ skipping 142 matching lines @@
   }
   return index;
 }
 
 int QuicStreamSequencer::Readv(const struct iovec* iov, size_t iov_len) {
   DCHECK(!blocked_);
   FrameMap::iterator it = buffered_frames_.begin();
   size_t iov_index = 0;
   size_t iov_offset = 0;
   size_t frame_offset = 0;
-  size_t initial_bytes_consumed = num_bytes_consumed_;
+  QuicStreamOffset initial_bytes_consumed = num_bytes_consumed_;
 
   while (iov_index < iov_len &&
          it != buffered_frames_.end() &&
          it->first == num_bytes_consumed_) {
     int bytes_to_read = min(iov[iov_index].iov_len - iov_offset,
                             it->second.size() - frame_offset);
 
     char* iov_ptr = static_cast<char*>(iov[iov_index].iov_base) + iov_offset;
     memcpy(iov_ptr,
            it->second.data() + frame_offset, bytes_to_read);
@@ skipping 13 matching lines @@
       frame_offset = 0;
     }
   }
   // We've finished copying.  If we have a partial frame, update it.
   if (frame_offset != 0) {
     buffered_frames_.insert(
         make_pair(it->first + frame_offset, it->second.substr(frame_offset)));
     buffered_frames_.erase(buffered_frames_.begin());
     RecordBytesConsumed(frame_offset);
   }
-  return num_bytes_consumed_ - initial_bytes_consumed;
+  return static_cast<int>(num_bytes_consumed_ - initial_bytes_consumed);
 }
 
 bool QuicStreamSequencer::HasBytesToRead() const {
   FrameMap::const_iterator it = buffered_frames_.begin();
 
   return it != buffered_frames_.end() && it->first == num_bytes_consumed_;
 }
 
 bool QuicStreamSequencer::IsClosed() const {
   return num_bytes_consumed_ >= close_offset_;
@@ skipping 77 matching lines @@
 }
 
 void QuicStreamSequencer::RecordBytesConsumed(size_t bytes_consumed) {
   num_bytes_consumed_ += bytes_consumed;
   num_bytes_buffered_ -= bytes_consumed;
 
   stream_->AddBytesConsumed(bytes_consumed);
 }
 
 }  // namespace net