Add tests for gfe/quic/spdy_utils::CopyAndValidateTrailers.

Add tests for gfe/quic/spdy_utils::CopyAndValidateTrailers.

Merge internal change: 159468423

R=rch@chromium.org

[wangyix1, 2017-06-28 19:05:03]

The CQ bit was checked by wangyix@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-06-28 19:05:36]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-06-28 19:09:09]

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

[commit-bot: I haz the power, 2017-06-28 19:09:10]

Dry run: Try jobs failed on following builders:
  ios-simulator on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bui...)
  mac_chromium_compile_dbg_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_comp...)

[wangyix1, 2017-06-28 20:00:34]

The CQ bit was checked by wangyix@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-06-28 20:01:02]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-06-28 20:04:28]

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

[commit-bot: I haz the power, 2017-06-28 20:04:29]

Dry run: Try jobs failed on following builders:
  chromium_presubmit on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)
  ios-simulator on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bui...)

[wangyix1, 2017-06-28 21:39:28]

The CQ bit was checked by wangyix@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-06-28 21:40:17]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-06-28 23:59:33]

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

[commit-bot: I haz the power, 2017-06-28 23:59:34]

Dry run: This issue passed the CQ dry run.

[Ryan Hamilton, 2017-06-29 02:53:05]

lgtm