handle large rects, rename helper

To fix gm/bigrect, needed to do adjust "largest" rect so it doesn't become empty when round-tripping with SkRect/SkIRect.
I renamed it after this.

Bug: skia:
Change-Id: I747782c8456da603cf298275d2300ea1996e7629
Reviewed-on: https://skia-review.googlesource.com/95563
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Yuqian Li <liyuqian@google.com>
9 files changed