[SPv175+] Don't output OverflowClip if InnerBorderRadiusClip already has the same rect

Previously we output three clip operations in SPv175 for
  <div style="overflow: hidden; border-radius: 5px; width: 100px; height: 100px">...</div>
which is one more than SPv1.

By omitting OverflowClip, now we output the same clip operations in
SPv175 and Spv1.

Bug: 814227
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
Change-Id: I8839d3af5180b017e20681c54ad94316632c08ab
Reviewed-on: https://chromium-review.googlesource.com/934923
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#539057}
15 files changed