Oilpan: Introduce GCTaskRunner

Oilpan: Introduce GCTaskRunner

MessageLoopInterruptor and PendingGCRunner are always created and destroyed at the same time.
This CL puts these two classes into GCTaskRunner.
This CL also renames PendingGCRunner to GCTaskObserver.

BUG=

Committed: https://crrev.com/b11e4bb09a938dce61a8a23517c119bb3ae5eb7d
Cr-Commit-Position: refs/heads/master@{#357058}

[haraken, 2015-10-29 15:58:05]

Description was changed from

==========
Oilpan: Introduce GCTaskRunner

MessageLoopInterruptor and PendingGCRunner are always created and destroyed at
the same time.
This CL puts these two classes into GCTaskRunner.
This CL also renames PendingGCRunner to GCTaskObserver.

BUG=
==========

to

==========
Oilpan: Introduce GCTaskRunner

MessageLoopInterruptor and PendingGCRunner are always created and destroyed at
the same time.
This CL puts these two classes into GCTaskRunner.
This CL also renames PendingGCRunner to GCTaskObserver.

BUG=
==========

[haraken, 2015-10-29 15:58:05]

haraken@chromium.org changed reviewers:
+ keishi@chromium.org

[haraken, 2015-10-29 15:58:15]

PTAL

[keishi, 2015-10-29 20:54:20]

LGTM

[haraken, 2015-10-30 05:34:51]

The CQ bit was checked by haraken@chromium.org

[commit-bot: I haz the power, 2015-10-30 05:35:27]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1419513007/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1419513007/1

[commit-bot: I haz the power, 2015-10-30 08:23:46]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-30 08:24:54]

Patchset 1 (id:??) landed as
https://crrev.com/b11e4bb09a938dce61a8a23517c119bb3ae5eb7d
Cr-Commit-Position: refs/heads/master@{#357058}