Revert "Oilpan: fix build after r197063, move HitTestCache to the heap."

Revert "Oilpan: fix build after r197063, move HitTestCache to the heap."

This reverts commit da27f0bb45d96705a51c875f0bf59d82db5f46c2.

The original HitTestCache change is being reverted due to it causing
a flaky test failure while I investigate it.

BUG=500514
TBR=sigbjornf@opera.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197115

[dtapuska, 2015-06-15 14:17:17]

The CQ bit was checked by dtapuska@chromium.org

[commit-bot: I haz the power, 2015-06-15 14:17:30]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1186843003/1

[commit-bot: I haz the power, 2015-06-15 14:17:32]

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

[commit-bot: I haz the power, 2015-06-15 14:17:33]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer,
_not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[Rick Byers, 2015-06-15 14:30:05]

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

[Rick Byers, 2015-06-15 14:30:05]

rubber stamp LGTM for revert

[dtapuska, 2015-06-15 14:31:11]

The CQ bit was checked by dtapuska@chromium.org

[commit-bot: I haz the power, 2015-06-15 14:31:52]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1186843003/1

[commit-bot: I haz the power, 2015-06-15 14:32:46]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197115