angular/angular.js — pull request #1315 by iwein (2012-08-30 04:49:40+00:00)
Title: Please accept my pull request that makes the time zone optional in the date filter

Problem with the current R_ISO8601_STR regex was that the time was optional, but the zone was not.
This results in the filter not formatting local date times, which it could easily do.

For example:
2012-08-30 -> formatted
2012-08-30T06:06:06.123Z -> formatted
2012-08-30T06:06:06.123 -> NOT formatted

A simple change in the regex fixes this. Arguably this is closer to the ISO8601 spec which specifies
local dates being in the "current time zone" and not requiring a Z. In any case it behaves more like
a user would expect.