[ios] Adds VoiceSearchProvider::IsVoiceSearchEnabled().

[ios] Adds VoiceSearchProvider::IsVoiceSearchEnabled().

The other provider methods must not be called if voice search is disabled.

BUG=656617
Committed: https://crrev.com/d2b3e48271c11701aae1fdb32188b3390664fa35
Cr-Commit-Position: refs/heads/master@{#428393}

[rohitrao (ping after 24h), 2016-10-28 15:06:44]

rohitrao@chromium.org changed reviewers:
+ kkhorimoto@chromium.org

[lpromero, 2016-10-28 16:31:50]

lpromero@chromium.org changed reviewers:
+ lpromero@chromium.org

[lpromero, 2016-10-28 16:31:50]

The CQ bit was checked by lpromero@chromium.org

[lpromero, 2016-10-28 16:31:50]

lgtm

[commit-bot: I haz the power, 2016-10-28 16:32:21]

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, 2016-10-28 16:54:47]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-10-28 17:21:44]

Description was changed from

==========
[ios] Adds VoiceSearchProvider::IsVoiceSearchEnabled().

The other provider methods must not be called if voice search is disabled.

BUG=656617
==========

to

==========
[ios] Adds VoiceSearchProvider::IsVoiceSearchEnabled().

The other provider methods must not be called if voice search is disabled.

BUG=656617

Committed: https://crrev.com/d2b3e48271c11701aae1fdb32188b3390664fa35
Cr-Commit-Position: refs/heads/master@{#428393}
==========

[commit-bot: I haz the power, 2016-10-28 17:21:46]

Patchset 1 (id:??) landed as
https://crrev.com/d2b3e48271c11701aae1fdb32188b3390664fa35
Cr-Commit-Position: refs/heads/master@{#428393}