[Oilpan] Refactoring: Rename GarbageCollectedBase to GarbageCollectedType

Refactoring: Rename GarbageCollectedBase to GarbageCollectedType.

For many templates, FooBarBase is used to describe a generic
template for FooBar.
This change is to avoid confusing names for the rule.

BUG=None

Committed: https://crrev.com/bc965582dc723bf48d1eab2746bc8c660092f17b
Cr-Commit-Position: refs/heads/master@{#352297}

[peria, 2015-10-05 05:12:28]

peria@chromium.org changed reviewers:
+ oilpan-reviews@chromium.org

[peria, 2015-10-05 05:12:28]

PTL

[haraken, 2015-10-05 05:13:14]

LGTM

[peria, 2015-10-05 05:18:01]

The CQ bit was checked by peria@chromium.org

[commit-bot: I haz the power, 2015-10-05 05:18:04]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1379603006/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1379603006/1

[commit-bot: I haz the power, 2015-10-05 06:55:55]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-05 06:56:43]

Patchset 1 (id:??) landed as
https://crrev.com/bc965582dc723bf48d1eab2746bc8c660092f17b
Cr-Commit-Position: refs/heads/master@{#352297}