Remove trace of MouseEventPreconnect field trial.

Remove trace of MouseEventPreconnect field trial.

The MouseEventPreconnect field trial has ended, but there is still a
trace of it remaining in ChromeBrowserFieldTrials. Remove it.

BUG=240959
TEST=chrome compiles

Committed: https://crrev.com/ba307d986145b46114c07657dba4b789e4501935
Cr-Commit-Position: refs/heads/master@{#322431}

[Adam Rice, 2015-03-26 12:31:50]

ricea@chromium.org changed reviewers:
+ kouhei@chromium.org

[kouhei (in TOK), 2015-03-26 12:32:34]

The CQ bit was checked by kouhei@chromium.org

[kouhei (in TOK), 2015-03-26 12:32:34]

lgtm

Thanks for cleaning up!

[commit-bot: I haz the power, 2015-03-26 12:32:40]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1037033002/1

[commit-bot: I haz the power, 2015-03-26 12:39:13]

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

[commit-bot: I haz the power, 2015-03-26 12:39:13]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[Adam Rice, 2015-03-26 13:19:01]

ricea@chromium.org changed reviewers:
+ thestig@chromium.org

[Adam Rice, 2015-03-26 13:19:02]

+thestig for OWNERS.

[Lei Zhang, 2015-03-26 18:22:37]

LGTM, thank you for noticing and removing.

[Lei Zhang, 2015-03-26 18:23:04]

The CQ bit was checked by thestig@chromium.org

[commit-bot: I haz the power, 2015-03-26 18:23:33]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1037033002/1

[commit-bot: I haz the power, 2015-03-26 18:26:55]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-26 18:27:47]

Patchset 1 (id:??) landed as
https://crrev.com/ba307d986145b46114c07657dba4b789e4501935
Cr-Commit-Position: refs/heads/master@{#322431}