Revert 282243 "Fix an issue that android Download Manager doesn'..."

Revert 282243 "Fix an issue that android Download Manager doesn'..."

> Fix an issue that android Download Manager doesn't handle OMA files correctly
>
> For OMA files, it looks like that android download manager cannot correctly download it.
> Some of the files cannot be downloaded, and some of the files downloaded has different binary content as the ones downloaed on chrome desktop.
> Bypass android download manager for OMA mime types.
>
> BUG=382698
>
> Review URL: https://codereview.chromium.org/331143010

TBR=tedchoc@chromium.org
BUG=382698
Committed: https://crrev.com/36ab8ba1abae1ab1d2059924969bf671797fa9d4
Cr-Commit-Position: refs/heads/master@{#294538}

[qinmin, 2014-09-11 18:06:57]

The CQ bit was checked by qinmin@chromium.org

[commit-bot: I haz the power, 2014-09-11 18:09:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/567733002/1

[commit-bot: I haz the power, 2014-09-12 00:36:36]

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

[commit-bot: I haz the power, 2014-09-12 00:36:36]

Exceeded time limit waiting for builds to trigger.

[qinmin, 2014-09-12 03:42:45]

The CQ bit was checked by qinmin@chromium.org

[commit-bot: I haz the power, 2014-09-12 03:43:07]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/567733002/1

[commit-bot: I haz the power, 2014-09-12 03:48:24]

Committed patchset #1 (id:1) as 3777f485b98a3072e1cceed9d6ed6d53eb163f57

[commit-bot: I haz the power, 2014-09-12 03:50:43]

Patchset 1 (id:??) landed as
https://crrev.com/36ab8ba1abae1ab1d2059924969bf671797fa9d4
Cr-Commit-Position: refs/heads/master@{#294538}