[OpenJDK 2D-Dev] Various fixes to pisces stroke widening code

[Jim Graham]

Sigh...

Pisces could really stand to upgrade to floats/doubles everywhere, for 
several reasons:

- FPU ops are likely as fast if not faster on modern hardware due to 
parallel execution of FP instructions alongside regular instructions.

- Don't have to worry about getting coordinates larger than 32K (I don't 
think this is well tested, but I imagine that Pisces will not deal with 
it very gracefully).

- Lots of code is greatly simplified not having to deal with the 
semantics of how to do fixed point multiplies, divides, and conversions.

I meant to do this during the original integration, but I wanted to get 
the task done as quickly as possible so that we could have an open 
source alternative to the closed Ductus code so I left that task for a 
later update.  But, now that a lot of work is being done on the code to 
fix it up, it might be better to do the float conversion now so that the 
maintenance is easier and before we end up creating a lot of new fixed 
point code.

My plate is full right now, but hopefully I can interest someone else in 
doing a cleanup cycle?  (Donning my Tom Sawyer hat... ;-)

			...jim