net: fix bug in compact HSTS representation.

net: fix bug in compact HSTS representation.

In r298580, I added a bug where jumps to the very beginning of the data (bit
offset zero) would be rejected. This was found by fuzzing.

BUG=none

Committed: https://crrev.com/f1fd1df2887acbe72ac107cad49506d430da9ae5
Cr-Commit-Position: refs/heads/master@{#300324}

[agl, 2014-10-17 21:59:27]

agl@chromium.org changed reviewers:
+ palmer@chromium.org

[palmer, 2014-10-17 22:04:16]

lgtm

[agl, 2014-10-17 22:05:51]

The CQ bit was checked by agl@chromium.org

[commit-bot: I haz the power, 2014-10-17 22:06:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/663903002/1

[commit-bot: I haz the power, 2014-10-17 22:56:22]

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

[commit-bot: I haz the power, 2014-10-17 22:56:22]

Try jobs failed on following builders:
  win_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/win_gpu_triggered...)

[agl, 2014-10-20 20:37:37]

The CQ bit was checked by agl@chromium.org

[commit-bot: I haz the power, 2014-10-20 20:39:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/663903002/1

[commit-bot: I haz the power, 2014-10-20 20:42:39]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-20 20:43:36]

Patchset 1 (id:??) landed as
https://crrev.com/f1fd1df2887acbe72ac107cad49506d430da9ae5
Cr-Commit-Position: refs/heads/master@{#300324}