Reland: Pass initDataType instead of contentType to OnNeedKey().

Reland: Pass initDataType instead of contentType to OnNeedKey().

BUG=224786
Cr-Commit-Position: refs/heads/master@{#297523}
(cherry picked from commit 2983dc91cc0bc7be6014f4bfc5cb19cc6e262a0b)

Committed: https://crrev.com/22851a415bff2a92fa24c2794ffc768188137a3c
Cr-Commit-Position: refs/heads/master@{#297872}

[sandersd (OOO until July 31), 2014-10-01 20:17:16]

sandersd@chromium.org changed reviewers:
+ ddorwin@chromium.org

[ddorwin, 2014-10-01 21:07:13]

Description nits:
* s/Revert revert/Reland/
* "The layout test that caused the revert has been updated (Blink revision
183020)."

Also, you could move the comment about the revert (and even the sentence above)
to your CL messages. If someone cares, they can always come to this CL or the
BUG to find them. That keeps the commit log simple and nearly identical to the
original commit that you are relanding.

[sandersd (OOO until July 31), 2014-10-01 21:09:10]

No changes, this should work now that the layout test has been updated.
(https://src.chromium.org/viewvc/blink?view=rev&revision=183020)

Revert was https://crrev.com/de394fa4553674e0aa522ce7c3483394f0f40d3d.

[ddorwin, 2014-10-01 21:15:01]

Thanks. rsLGTM of cherry-pick - I briefly skimmed it.

[ddorwin, 2014-10-01 21:15:27]

^LGTM

[sandersd (OOO until July 31), 2014-10-02 17:50:22]

The CQ bit was checked by sandersd@chromium.org

[commit-bot: I haz the power, 2014-10-02 17:52:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/617333003/1

[commit-bot: I haz the power, 2014-10-02 18:49:58]

Committed patchset #1 (id:1) as 3ede2a91982fe5863e4427c371192551ef751e38

[commit-bot: I haz the power, 2014-10-02 18:50:44]

Patchset 1 (id:??) landed as
https://crrev.com/22851a415bff2a92fa24c2794ffc768188137a3c
Cr-Commit-Position: refs/heads/master@{#297872}