Cherry picked from e348b406 .

Adjusts unit test regarding exception in injected scripts so that it accounts for the exception being thrown in an event loop for remote scripts

Opera 12.0 still implements an older version of the DOM so cloneNode cannot be called without an argument

Tweaks the logic in the 304-related unit tests so that they pass for versions of Opera that support manual 304 handling as well as for those that don't

Fixes comments per @rwldrn. Makes sure failing requests from local protocol yields status 404, not 0.

Check removed in the initial 2.0 refactor but Chrome still needs it. No effective way to unit test; see the test case in #13143.

Previous versions of grunt-contrib-watch did not support editors that used safe-writes (vim, etc..).

Reverts the following commits:

commit f717226b
Author: Rick Waldron <waldron.rick@gmail.com>
Date:   Mon Dec 31 18:06:38 2012 -0500

Only splice from internal arrays when item actually exists.

commit b9cdc413
Author: Rick Waldron <waldron.rick@gmail.com>
Date:   Mon Dec 31 16:20:35 2012 -0500

Updates to data.js re-write to pass events and manipulation

commit d1de3000
Author: Rick Waldron <waldron.rick@gmail.com>
Date:   Mon Dec 31 15:09:45 2012 -0500

2.0: Rewrite data.js

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>