Actually we are already correct for the above case because the background are painted by FillRoundedRect without clipping. There are other cases that we use RoundedInnerRectClipper to clip background painting for SPv1. We need to issue real clip drawing operation for SPv175+ in the cases.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/59b8d15c0b235802cd8b57b776c8c096a5e3c384

commit 59b8d15c0b235802cd8b57b776c8c096a5e3c384
Author: Xianzhu Wang <wangxianzhu@chromium.org>
Date: Wed Dec 13 23:59:56 2017

[SPv175+] Output InnerBorderRadiusClip for replaced elements if needed

Replaced elements (except SVGRoot which uses the normal overflow clip/
border-radius clip rule) with border-radius will apply border radius clip
on their foreground, so we need to output InnerBorderRadiusClip for them,
and set proper chunk properties when painting their foregrounds.

Bug:  794295 
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
Change-Id: I206db7fcf55a99187cf1f8961f5f286d482f1bf2
Reviewed-on: https://chromium-review.googlesource.com/823177
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#523940}
[modify] https://crrev.com/59b8d15c0b235802cd8b57b776c8c096a5e3c384/third_party/WebKit/LayoutTests/TestExpectations
[modify] https://crrev.com/59b8d15c0b235802cd8b57b776c8c096a5e3c384/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.cpp
[modify] https://crrev.com/59b8d15c0b235802cd8b57b776c8c096a5e3c384/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilderTest.cpp
[modify] https://crrev.com/59b8d15c0b235802cd8b57b776c8c096a5e3c384/third_party/WebKit/Source/core/paint/ReplacedPainter.cpp