Extends DecimalFormat.format optimization to the HALF_UP/HALF_DOWN rounding cases

The DecimalFormat.format(double, ...) optimization that has been provided in JDK (see JDK-7050528) is available only for the HALF_EVEN rounding. HALF_UP and HALF_DOWN rounding still use the slow path.

While HALF_EVEN rounding mode is the rounding case that is mainly and mostly used, this means that there are throughput inconsistencies for floating-point values that are in the integer range depending on the rounding case used.

Recent customer feedback has shown that HALF_UP and HALF_DOWN rounding cases are also used in business applications.

Extending this optimization to the HALF_UP and HALF_DOWN rounding does not need a lot of work.

To avoid any usability issue between these rounding modes due to this throughput difference (x10 factor) it would be good to extend the optimization to HALF_UP/_DOWN rounding cases.