Fix HtmlTimeFormatter

HtmlTimeFormatter::calendarNameNeeded was using a wrong approach to
parse the year from the ISO string. That resulted in the
calendarmodel-hint always shown for dates like e.g. 2014-10-10 where it is
not necessary to show the hint.

Change-Id: Iaba698ed4cfb91c7452b144f28446947b9ab2c1a
Merge "Fix HtmlTimeFormatter"