Revert of Add ScriptForbiddenScope to weak callbacks of DOM wrappers

Revert of Add ScriptForbiddenScope to weak callbacks of DOM wrappers (https://codereview.chromium.org/368853002/)

Reason for revert:
This CL regressed performance.  We'll need to re-think how to handle this situation

Original issue's description:
> Add ScriptForbiddenScope to weak callbacks of DOM wrappers
> 
> It's dangerous to allow arbitrary JavaScript to run during a V8 GC.
> 
> BUG=389445
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=177457

[abarth-chromium, 2014-07-30 06:01:05]

Created Revert of Add ScriptForbiddenScope to weak callbacks of DOM wrappers

[commit-bot: I haz the power, 2014-07-30 06:01:20]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/abarth@chromium.org/430763002/1

[commit-bot: I haz the power, 2014-07-30 06:01:21]

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

[commit-bot: I haz the power, 2014-07-30 06:01:22]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer or
a provisional committer, _not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[abarth-chromium, 2014-07-30 06:19:10]

The CQ bit was checked by abarth@chromium.org

[commit-bot: I haz the power, 2014-07-30 06:19:36]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/abarth@chromium.org/430763002/1

[commit-bot: I haz the power, 2014-07-30 06:19:37]

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

[commit-bot: I haz the power, 2014-07-30 06:19:38]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer or
a provisional committer, _not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.