Revert of Isolate extensions_browsertests

Revert of Isolate extensions_browsertests (patchset #7 id:120001 of https://codereview.chromium.org/869783004/)

Reason for revert:
This CL seem to cause the failure in extension browser test in Windows Vista SP2

Original issue's description:
> Isolate extensions_browsertests
>
> R=maruel@chromium.org, yoz@chromium.org
> TBR=jam@chromium.org
> BUG=98637
>
> Committed: https://crrev.com/d1caf97fe8db47e5c76043bccbf4dd4a42265831
> Cr-Commit-Position: refs/heads/master@{#312993}

TBR=maruel@chromium.org,yoz@chromium.org,scottmg@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=98637
Committed: https://crrev.com/c25902f538732f8bcfc651f72c2a5af043e7b9bd
Cr-Commit-Position: refs/heads/master@{#313062}

[kaliamoorthi, 2015-01-26 12:43:57]

Created Revert of Isolate extensions_browsertests

[commit-bot: I haz the power, 2015-01-26 12:44:39]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/876633002/1

[commit-bot: I haz the power, 2015-01-26 12:45:23]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-01-26 12:46:17]

Patchset 1 (id:??) landed as
https://crrev.com/c25902f538732f8bcfc651f72c2a5af043e7b9bd
Cr-Commit-Position: refs/heads/master@{#313062}

[scottmg, 2015-01-26 17:48:46]

Thanks, lgtm. Sorry for leaving it broken so long.

(Need to try all permutations of OS's and Debug/Release when isolating it seems
-- Windows is too sneaky.)