Pass virtual/scalefactor200/css3/filters/effect-reference-subregion-hw.html

It appears that this expected.txt is causing the failure on Mac:
https://ci.chromium.org/p/chromium/builders/ci/Mac10.12%20Tests/23664
https://ci.chromium.org/p/chromium/builders/ci/Mac10.13%20Tests%20%28dbg%29/12244

Deleting this should work.

Bug: 968791
Change-Id: I6134b3c67fa38a316b66ab97be2eb7a46525d364
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1645378Reviewed-by: Robert Ma <robertma@chromium.org>
Commit-Queue: Xida Chen <xidachen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#666315}

third_party/blink/web_tests/platform/mac/virtual/scalefactor200/css3/filters/effect-reference-subregion-hw-expected.txt

-Content-Type: text/plain
-#EOF