Fix crashes on iOS related to using window.performance and reading window.location.href in a UIWebV…

Fix iOS crash related to window.performance

Fix crashes on iOS related to using window.performance and reading
window.location.href in a UIWebView. You must set the global variable
distiller_on_ios=true prior to evaluating the distiller.

BUG=
R=mdjones@chromium.org

Committed: e55d6a44018f67a43a41493db0822a41f958c797

[mdjones, 2015-10-10 00:46:53]

mdjones@chromium.org changed reviewers:
+ mdjones@chromium.org

[mdjones, 2015-10-10 01:03:09]

lgtm

[mdjones, 2015-10-10 01:14:46]

Before I land this, are you okay with your @google.com email being used on
github?

[wychen, 2015-10-10 03:05:16]

On 2015/10/10 01:14:46, mdjones wrote:
> Before I land this, are you okay with your @google.com email being used on
> github?

Or you could specify your preferred author field, like:
George Nachman <georgen@google.com>

[georgen, 2015-10-13 17:27:28]

On 2015/10/10 03:05:16, wychen wrote:
> On 2015/10/10 01:14:46, mdjones wrote:
> > Before I land this, are you okay with your @google.com email being used on
> > github?
> 
> Or you could specify your preferred author field, like:
> George Nachman <mailto:georgen@google.com>

I'm find with that email being used on github. It's already there many times
over.

[mdjones, 2015-10-13 17:48:14]

Committed patchset #2 (id:20001) manually as
e55d6a44018f67a43a41493db0822a41f958c797 (presubmit successful).