Add a few extra tests for throttling corner cases

Add a few extra tests for throttling corner cases

While investigating crbug.com/620857 I noticed we were lacking
tests for some corner cases of throttling and timer suspension.

BUG=620857
Committed: https://crrev.com/26c1102c976aeb0ae91bed0d3f7f7abd92a41e20
Cr-Commit-Position: refs/heads/master@{#401618}

[alex clarke (OOO till 29th), 2016-06-20 11:06:57]

alexclarke@chromium.org changed reviewers:
+ skyostil@chromium.org

[Sami, 2016-06-20 11:07:56]

lgtm

[alex clarke (OOO till 29th), 2016-06-23 15:16:34]

The CQ bit was checked by alexclarke@chromium.org

[commit-bot: I haz the power, 2016-06-23 15:16:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2081663002/1

[commit-bot: I haz the power, 2016-06-23 16:02:25]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-06-23 16:06:48]

Description was changed from

==========
Add a few extra tests for throttling corner cases

While investigating crbug.com/620857 I noticed we were lacking
tests for some corner cases of throttling and timer suspension.

BUG=620857
==========

to

==========
Add a few extra tests for throttling corner cases

While investigating crbug.com/620857 I noticed we were lacking
tests for some corner cases of throttling and timer suspension.

BUG=620857

Committed: https://crrev.com/26c1102c976aeb0ae91bed0d3f7f7abd92a41e20
Cr-Commit-Position: refs/heads/master@{#401618}
==========

[commit-bot: I haz the power, 2016-06-23 16:06:49]

Patchset 1 (id:??) landed as
https://crrev.com/26c1102c976aeb0ae91bed0d3f7f7abd92a41e20
Cr-Commit-Position: refs/heads/master@{#401618}