Land Recent QUIC Changes.

Land Recent QUIC Changes.

Change QUIC's RTO implementation. Protected by FLAGS_quic_use_new_rto.

Decides whether to invoke SendAlgorithmInterface's
OnRetransmissionTimeout after an ack has been received instead of
pro-actively invoking it and then having to revert it.

Fix a minor QUIC bug when both quic_use_new_rto and
quic_rto_uses_last_sent were enabled, a spurious retransmission didn't
expire the SRTT.

Merge internal change: 83625311, 83966746

https://codereview.chromium.org/841603005/

Remove unused original transmission stats from QuicAckNotifier.
No behavior change.

Merge internal change: 83598791
https://codereview.chromium.org/798873005/

Removing quic version 21

Merge internal change: 83551025
https://codereview.chromium.org/786953009/

Fixes typo, changing OnSpuriousPacketRetransmition to
OnSpuriousPacketRetransmission.

Merge internal change: 83546153
https://codereview.chromium.org/837273004/

Adds an alarm for sending a QUIC FEC packet.

This CL adds an alarm for sending an FEC packet. The alarm is based on
the connection's SRTT, and is set when the first FEC protected packet in
an FEC group is sent. This alarm puts some time between the sending of
an FEC protected packet and the corresponding FEC packet, to reduce the
probability of both these packets getting dropped in the network.

Merge internal change: 83543120
https://codereview.chromium.org/839163003/

Tell the QUIC AckNotifierManager about packets on serialization, rather
than when successfully sent.
Protected by ENABLEd FLAGS_quic_ack_notifier_informed_on_serialized.

Merge internal change: 83525991
https://codereview.chromium.org/854463003/

R=rch@chromium.org
BUG=448688
Committed: https://crrev.com/5d9c02ca6f59328fe2191422fa950301187a36ff
Cr-Commit-Position: refs/heads/master@{#311789}

[ramant (doing other things), 2015-01-15 01:21:58]

On 2015/01/14 21:44:50, ramant wrote:

Hi Ryan,
  Working on a fix for the race in
EndToEndTest::AckNotifierWithPacketLossAndBlockedSocket where the code was
restoring the value of FLAGS_quic_ack_notifier_informed_on_serialized at the end
of the test. Another thread is still reading the old value of this FLAG. (In
this case, the default value of the FLAG is true, we are restoring it back to
true from true).

[ramant (doing other things), 2015-01-15 02:32:53]

Patchset #2 (id:20001) has been deleted

[ramant (doing other things), 2015-01-15 02:35:46]

Hi Ryan,
  Verified pausing and resuming the server (similar to other unittests) fixes
the race. 

PTAL.

[Ryan Hamilton, 2015-01-15 20:27:15]

lgtm

[ramant (doing other things), 2015-01-15 21:28:08]

The CQ bit was checked by rtenneti@chromium.org

[commit-bot: I haz the power, 2015-01-15 21:29:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/849123003/60001

[commit-bot: I haz the power, 2015-01-16 00:46:01]

Committed patchset #3 (id:60001)

[commit-bot: I haz the power, 2015-01-16 00:48:19]

Patchset 3 (id:??) landed as
https://crrev.com/5d9c02ca6f59328fe2191422fa950301187a36ff
Cr-Commit-Position: refs/heads/master@{#311789}