The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6ba0f425818ef98dc2f82decae9d61e5d1d2edcd

commit 6ba0f425818ef98dc2f82decae9d61e5d1d2edcd
Author: zhongyi <zhongyi@chromium.org>
Date: Tue Aug 23 05:20:04 2016

QUIC: Add packet_reader_yield_after_duration_milliseconds field trial param.

When this field param is provided, QUIC packet reader will set yield_after_time_ packet_reader_yield_after_duration_milliseconds. Otherwise, set to 20ms.
BUG= 640074 

Review-Url: https://codereview.chromium.org/2270583002
Cr-Commit-Position: refs/heads/master@{#413670}

[modify] https://crrev.com/6ba0f425818ef98dc2f82decae9d61e5d1d2edcd/components/network_session_configurator/network_session_configurator.cc
[modify] https://crrev.com/6ba0f425818ef98dc2f82decae9d61e5d1d2edcd/components/network_session_configurator/network_session_configurator_unittest.cc
[modify] https://crrev.com/6ba0f425818ef98dc2f82decae9d61e5d1d2edcd/net/http/http_network_session.cc
[modify] https://crrev.com/6ba0f425818ef98dc2f82decae9d61e5d1d2edcd/net/http/http_network_session.h
[modify] https://crrev.com/6ba0f425818ef98dc2f82decae9d61e5d1d2edcd/net/quic/chromium/quic_stream_factory.cc
[modify] https://crrev.com/6ba0f425818ef98dc2f82decae9d61e5d1d2edcd/net/quic/chromium/quic_stream_factory.h
[modify] https://crrev.com/6ba0f425818ef98dc2f82decae9d61e5d1d2edcd/net/quic/chromium/quic_stream_factory_test.cc

By default, we have changed packet reader to yield after 2ms. Manually attach the change log here. 

Default packet reader yield time to 2ms as stable experimental results
shows performance improvement.

Bug: 
Change-Id: I7f40d51e15b19dd5ae6d1b56b9a0167aa7f80b11
Reviewed-on: https://chromium-review.googlesource.com/582327
Commit-Queue: Zhongyi Shi <zhongyi@chromium.org>
Reviewed-by: Ryan Hamilton <rch@chromium.org>
Cr-Commit-Position: refs/heads/master@{#489413}