Examples of failures: https://codereview.chromium.org/2600613002/#ps20001 on  linux_trusty_blink_rel and linux_chromium_rel_ng.

Will try to rebaseline again. Will close this bug if the new rebaseline succeeds.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/187123679eacc2c34143415a5ba69eaf456cd759

commit 187123679eacc2c34143415a5ba69eaf456cd759
Author: wangxianzhu <wangxianzhu@chromium.org>
Date: Fri Dec 23 18:48:19 2016

Rebaseline virtual/scalefactor200/fast/hidpi/static/popup-menu-with-scrollbar-appearance.html

BUG= 676754 
TBR=oshima@chromium.org
NOTRY=true

Review-Url: https://codereview.chromium.org/2596423003
Cr-Commit-Position: refs/heads/master@{#440647}

[modify] https://crrev.com/187123679eacc2c34143415a5ba69eaf456cd759/third_party/WebKit/LayoutTests/platform/linux/virtual/scalefactor200/fast/hidpi/static/popup-menu-with-scrollbar-appearance-expected.png

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e51f44db8ce4d3b9f20a53aa530293f348600927

commit e51f44db8ce4d3b9f20a53aa530293f348600927
Author: wangxianzhu <wangxianzhu@chromium.org>
Date: Mon Dec 26 19:06:39 2016

Remove failure expectation of virtual/scalefactor200/fast/hidpi/static/popup-menu-with-scrollbar-appearance.html

It has been passing since the last rebaseline:
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=webkit_tests&tests=virtual%2Fscalefactor200%2Ffast%2Fhidpi%2Fstatic%2Fpopup-menu-with-scrollbar-appearance.html

BUG= 676754 
TBR=oshima@chromium.org

Review-Url: https://codereview.chromium.org/2602703002
Cr-Commit-Position: refs/heads/master@{#440718}

[modify] https://crrev.com/e51f44db8ce4d3b9f20a53aa530293f348600927/third_party/WebKit/LayoutTests/TestExpectations