- we want functions like isEmpty() to return true if NANs are
involved in the Rect
- also clean-up the intersect familly of calls
- minor cleanup in the int32_t Rect as well
These played a role in http://b/5331198.
Bug: 5331198
Change-Id: I5369725ab482e4b83da9f1bd4cee5256e5de75b2