Made IndexedDB's comparators public.

Made IndexedDB's comparators public.

Moved IndexedDBBackingStore::Comparator and LevelDBDatabase::ComparatorAdapter
up into their respective class definitions. This allows them to be instantiated
(or derived from). This change is necessary in order to facilitate the
authoring of an IndexedDB diagnostic utility application. The design of LevelDB
is such that the same comparator must be used when opening a LevelDB that was
used to create it.

BUG=

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=259867

[cmumford, 2014-03-26 18:53:21]

No implementation changes, only making two classes public.

[dgrogan, 2014-03-26 19:34:02]

lgtm

[cmumford, 2014-03-26 21:32:14]

The CQ bit was checked by cmumford@chromium.org

[commit-bot: I haz the power, 2014-03-26 21:33:57]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/cmumford@chromium.org/213263004/1

[commit-bot: I haz the power, 2014-03-27 03:53:03]

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

[commit-bot: I haz the power, 2014-03-27 03:53:04]

Commit queue rejected this change because the description was changed
between the time the change entered the commit queue and the time it
was ready to commit. You can safely check the commit box again.

[cmumford, 2014-03-27 15:28:07]

The CQ bit was checked by cmumford@chromium.org

[commit-bot: I haz the power, 2014-03-27 15:28:16]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/cmumford@chromium.org/213263004/1

[commit-bot: I haz the power, 2014-03-27 15:30:10]

Change committed as 259867