Before this fix, date categories imported in oox's DataSourceContext were
stored as formatted strings according to number format code in <c:formatCode>
under the <c:cat> tree. As a result chart2 could not recognize them
as dates. This causes problems like:
* The axis that is linked to date categories cannot use the
scaling/range-selection(min/max)/increments specs mentioned as axis
properties. This results in distorted/unreadable chart renders w.r.t
the date axis.
* No re-formatting is attempted as per the number format provided for axis.
This patch introduces a role qualifer argument to the XDataProvider
interface method createDataSequenceByValueArray to support categories of
date type via this method.
When exporting to oox, write date categories and format code under
<c:cat>
<c:numRef>
<c:numCache>
This patch also fixes some discrepancies in date axis interval
computation (auto mode) found by already existing unit tests.
Change-Id: Ibc53b0a56fdddba80ba452d5567ce98d80460ea7
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/121525
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
