Simplify scan converter's args

All scan converters need an SkIRect clipBounds and a bool
containedInClip.  However, we previously sent in an SkRegion
and a SkIRect*, and convert them into clipBounds and
containedInClip all over the places. This CL converts them
only once inside do_fill_path and change all args to SkIRect
and bool.

Bug: skia:
Change-Id: I05f1d76322942d8817860fd33991f7f7ce918e7c
Reviewed-on: https://skia-review.googlesource.com/52741
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Yuqian Li <liyuqian@google.com>
4 files changed