Convert prefix search in UserScript code to use base::StartsWith()

Convert prefix search in UserScript code to use base::StartsWith()

Using string.find('pattern') == 0 is O(|string|), so don't do that.

BUG=622464
Test=None, internal only change.

Committed: https://crrev.com/28acad804b4c3592ae4aa6465302d895c750c7a6
Cr-Commit-Position: refs/heads/master@{#401451}

[lazyboy, 2016-06-22 21:35:54]

lazyboy@chromium.org changed reviewers:
+ asargent@chromium.org

[asargent_no_longer_on_chrome, 2016-06-22 22:19:45]

nice catches!

lgtm

[lazyboy, 2016-06-22 22:36:45]

The CQ bit was checked by lazyboy@chromium.org

[commit-bot: I haz the power, 2016-06-22 22:37:32]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2096433002/1

[commit-bot: I haz the power, 2016-06-22 23:14:42]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-06-22 23:16:54]

Description was changed from

==========
Convert prefix search in UserScript code to use base::StartsWith()

Using string.find('pattern') == 0 is O(|string|), so don't do that.

BUG=622464
Test=None, internal only change.
==========

to

==========
Convert prefix search in UserScript code to use base::StartsWith()

Using string.find('pattern') == 0 is O(|string|), so don't do that.

BUG=622464
Test=None, internal only change.

Committed: https://crrev.com/28acad804b4c3592ae4aa6465302d895c750c7a6
Cr-Commit-Position: refs/heads/master@{#401451}
==========

[commit-bot: I haz the power, 2016-06-22 23:16:56]

Patchset 1 (id:??) landed as
https://crrev.com/28acad804b4c3592ae4aa6465302d895c750c7a6
Cr-Commit-Position: refs/heads/master@{#401451}