HPACK: encode :pseudo and indexed headers first.

HPACK: encode :pseudo and indexed headers first.

HTTP/2 header compression HPACK draft-09 requires pseudo-headers (names
starting with ":") to be encoded before regular headers.  Also, headers that
are in the header table are emitted before others, to avoid eviction before
they could be used.

This lands server change 74039742 by bnc.

BUG=395635
Committed: https://crrev.com/fb8795450e61e29750975a07a956be75b38a2fcd
Cr-Commit-Position: refs/heads/master@{#293290}

[Bence, 2014-09-03 19:54:09]

bnc@chromium.org changed reviewers:
+ jgraettinger@chromium.org

[Bence, 2014-09-03 19:54:09]

PTAL

[Johnny, 2014-09-03 21:28:22]

lgtm

[Bence, 2014-09-04 00:39:28]

The CQ bit was checked by bnc@chromium.org

[commit-bot: I haz the power, 2014-09-04 00:41:44]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/bnc@chromium.org/537663002/1

[commit-bot: I haz the power, 2014-09-04 02:56:38]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-09-04 02:56:38]

Try jobs failed on following builders:
  android_clang_dbg_recipe on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/android_clang_d...)

[Bence, 2014-09-04 12:35:27]

The CQ bit was checked by bnc@chromium.org

[commit-bot: I haz the power, 2014-09-04 12:37:16]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/bnc@chromium.org/537663002/1

[commit-bot: I haz the power, 2014-09-04 13:09:07]

Committed patchset #1 (id:1) as 4e2559eb73fcf0f8de6a004cb2771fdc2de5adbf

[commit-bot: I haz the power, 2014-09-10 03:31:06]

Patchset 1 (id:??) landed as
https://crrev.com/fb8795450e61e29750975a07a956be75b38a2fcd
Cr-Commit-Position: refs/heads/master@{#293290}