Revert of Restore FileSystemProviderApiTest.BigFile.

Revert of Restore FileSystemProviderApiTest.BigFile. (patchset #1 id:1 of https://codereview.chromium.org/925213002/)

Reason for revert:
FileSystemProviderApiTest.BigFile is still failing, about 98% of runs on cros_trunk bot.

Original issue's description:
> Restore FileSystemProviderApiTest.BigFile.
>
> This test is not more flaky than other tests. There seem to be some test
> launching issue. Sometimes api tests do not start from time to time. It's
> not common though.
>
> Enabling the test, as it's better to have flaky test than no test. The issue
> with launching tests is tracked separately.
>
> TEST=browser_tests: *FileSystemProviderApiTest.BigFile*
> BUG=458122
>
> Committed: https://crrev.com/fae5f10535ecd3215d1e924505301562ed49744a
> Cr-Commit-Position: refs/heads/master@{#316429}

TBR=hirono@chromium.org,mtomasz@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=458122
Committed: https://crrev.com/95a5170e59f45c65403a833d0f12cbd6922d7d96
Cr-Commit-Position: refs/heads/master@{#317600}

[flackr, 2015-02-23 17:08:05]

Created Revert of Restore FileSystemProviderApiTest.BigFile.

[commit-bot: I haz the power, 2015-02-23 17:09:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/952623002/1

[commit-bot: I haz the power, 2015-02-23 17:09:42]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-23 17:10:23]

Patchset 1 (id:??) landed as
https://crrev.com/95a5170e59f45c65403a833d0f12cbd6922d7d96
Cr-Commit-Position: refs/heads/master@{#317600}