GregorianCalendar doesn't work with large +ve/-ve time values

[Stephen Crawley]

Folks,

There has been a fair bit of discussion about Date-related bugs
recently.  I'd like to draw your attention to the long-standing #9495
bug against java.util.GregorianCalendar which fails when you try
to convert a large +ve or -ve millisecond value to a Date.

There is a new(-ish) Mauve testcase that exercises GregorianCalendar
millisecond conversion across its range of input values:

    gnu.testlet.java.util.GregorianCalendar.conversion.java

The root cause of the bug is that the conversion calculations are done
using 'int' instead of 'long'.  For large millisecond values, some of
the calculations are wrapping around.

-- Steve