Remove trivially-true checks in quic_framer.cc

Remove trivially-true checks in quic_framer.cc

There were several places in this file where an error code value
was checked to see if it was less than QUIC_NO_ERROR or
QUIC_STREAM_NO_ERROR, which are both 0. On some compilers this
causes a warning, because such checks are trivially true.

BUG=424334
TEST=net_unittests
R=rch@chromium.org

Committed: https://crrev.com/6e7ef22cb8a5aef89036aeb7d7129fa5890a9480
Cr-Commit-Position: refs/heads/master@{#300368}

[Chris Masone, 2014-10-20 18:55:10]

I'm not necessarily convinced this is the right thing to do, as the current code
would still Do The Right Thing even if QUIC_NO_ERROR no longer equals 0. Is
there any risk of that? If so, maybe I could figure out another way to make the
compiler happy while still checking this condition.

[Ryan Hamilton, 2014-10-20 20:55:10]

lgtm

[Chris Masone, 2014-10-20 22:17:49]

The CQ bit was checked by cmasone@chromium.org

[commit-bot: I haz the power, 2014-10-20 22:22:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/662513007/1

[commit-bot: I haz the power, 2014-10-20 22:47:30]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-20 22:48:39]

Patchset 1 (id:??) landed as
https://crrev.com/6e7ef22cb8a5aef89036aeb7d7129fa5890a9480
Cr-Commit-Position: refs/heads/master@{#300368}