Move Preload enum to BufferedDataSource.

Move Preload enum to BufferedDataSource.

Moving the Preload out of the content namespace and into BufferedDataSource
since that class is the primary reason this enum exists.

BUG=408338
Committed: https://crrev.com/a5081a4c324d1f817523f58be4a99d57cb279d74
Cr-Commit-Position: refs/heads/master@{#292503}

[acolwell GONE FROM CHROMIUM, 2014-08-28 21:48:36]

acolwell@chromium.org changed reviewers:
+ scherkus@chromium.org

[scherkus (not reviewing), 2014-08-28 21:51:37]

lgtm

[acolwell GONE FROM CHROMIUM, 2014-08-28 21:53:00]

The CQ bit was checked by acolwell@chromium.org

[commit-bot: I haz the power, 2014-08-28 21:53:46]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/acolwell@chromium.org/512413002/1

[commit-bot: I haz the power, 2014-08-28 23:42:59]

Committed patchset #1 (id:1) as e88b68784938607246b48e1b8f4381b9df5e8ae4

[commit-bot: I haz the power, 2014-09-10 03:03:44]

Patchset 1 (id:??) landed as
https://crrev.com/a5081a4c324d1f817523f58be4a99d57cb279d74
Cr-Commit-Position: refs/heads/master@{#292503}