[PE] Fix hit-test of zoomed <clipPath> 'clip-path'

<clipPath> geometry is not subjected to zoom, so the hit-test location
and reference box has to be adjusted to make the coordinate spaces
match.

Bug: 800605
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
Change-Id: Ic03e24f0289a5019ea722e3931f6217d918a1b56
Reviewed-on: https://chromium-review.googlesource.com/859784
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#528743}
2 files changed