[touch-events] Spec should be explicit on whether the of elements in TouchLists is relevant (#13)

I believe the order of TouchList entries is supposed to be irrelevant.  However some sites (eg. [this one](http://mmeiers.github.io/content-multitouchimages/)) make assumptions about a given touch ID remaining at the same index in the TouchList from event to event.  There was a special case in blink where we weren't preserving order, and we're going to [fix this](https://code.google.com/p/chromium/issues/detail?id=463747).

In what cases is the ordering preserved in existing browsers?  Should we just make that part of the spec so that sites can depend on it?  It can certainly simplify some coding patterns.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/touch-events/issues/13