Fix infinite loop in SkRTree::insert()

When aspectRatio is not finite, insert() can fall into an infinite loop.
This happens if you pass SkRect::MakeLargest() to the factory as bounds.

BUG=skia:5974

Change-Id: Ibcc9e5c5943c718608d4c1448305f7b8f11413bc
Reviewed-on: https://skia-review.googlesource.com/11784
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>
2 files changed