shape ops work in progress

shape ops work in progress

Try to fix the 32 bit build by making some math
decisions more robust.

Rewrite the cubic intersection special case that
detects if only end points are shared.

Rewrite the angle sort setup that computes whether
a cubic bends to the left or right.

git-svn-id: http://skia.googlecode.com/svn/trunk@8726 2bbb7eff-a529-9590-31e7-b0007b416f81