Bug 217812 – REGRESSION(268444?): [ Win10 wk1 ews ] individual transform properties tests are failing

• Component: New Bugs
• Status: NEW

[Karl Rackler]

Description:
transforms/2d/scale-change-composited.html

This issue does not happen on post-commit bots and the failure only presents on ews.

The first failure that I see on ews was 10/15/20 test transforms/2d/scale-change-composited.html failed on clean tree run in https://ews-build.webkit.org/#/builders/10/builds/39011.

EWS History:
https://ews-build.webkit.org/#/builders/10/builds/39011
https://ews-build.webkit.org/#/builders/10/builds/39013
https://ews-build.webkit.org/#/builders/10/builds/39012
https://ews-build.webkit.org/#/builders/10/builds/39014
https://ews-build.webkit.org/#/builders/10/builds/39020
https://ews-build.webkit.org/#/builders/10/builds/39024
https://ews-build.webkit.org/#/builders/10/builds/39029
https://ews-build.webkit.org/#/builders/10/builds/39032
https://ews-build.webkit.org/#/builders/10/builds/39034
https://ews-build.webkit.org/#/builders/10/builds/39038
https://ews-build.webkit.org/#/builders/10/builds/39050
https://ews-build.webkit.org/#/builders/10/builds/39051
https://ews-build.webkit.org/#/builders/10/builds/39057
https://ews-build.webkit.org/#/builders/10/builds/39056
https://ews-build.webkit.org/#/builders/10/builds/39078
https://ews-build.webkit.org/#/builders/10/builds/39081
https://ews-build.webkit.org/#/builders/10/builds/39084

Image Results:
https://ews-build.s3-us-west-2.amazonaws.com/Windows-EWS/r411549-39084/transforms/2d/scale-change-composited-diffs.html

[Radar WebKit Bug Importer]

<rdar://problem/70374675>

[Karl Rackler]

I have marked this test as skip while this issue is investigated.
https://trac.webkit.org/changeset/268580/webkit

[Karl Rackler]

The same issue is also happening with test transforms/2d/rotate-change-composited.html

Same history

Image Results:
https://ews-build.s3-us-west-2.amazonaws.com/Windows-EWS/r411549-39084/transforms/2d/scale-change-composited-diffs.html

I have marked this/these test(s as skip while this issue is investigated.
https://trac.webkit.org/changeset/268582/webkit

[Karl Rackler]

One more from this group is also affected the same way.  Test transforms/2d/translate-change-composited.html.

Same history as the other two tests.

Image Results:
https://ews-build.s3-us-west-2.amazonaws.com/Windows-EWS/r411549-39084/transforms/2d/translate-change-composited-diffs.html

I have marked this test as skip while this issue is investigated.
https://trac.webkit.org/changeset/268584/webkit

[Karl Rackler]

Description:
transforms/2d/scale-change-composited.html
transforms/2d/rotate-change-composited.html
transforms/2d/translate-change-composited.html

I went back further and can see build https://ews-build.webkit.org/#/builders/10/builds/38853 appears to be the first occurrence.

Around that same time period commit r268444 was made.  This is were the test were added.

The commit has to do with transform-origin is applied on top of invidivual CSS transform properties on composited layers, which could have introduced the flakiness.  

The change was introduced here https://trac.webkit.org/changeset/268444/webkit.

[Karl Rackler]

Description:
transforms/2d/rotate-composited.html 

Same symptoms as the others in the group.

I have marked this test as skip while this issue is investigated.
REGRESSION(268444?): [ Win10 wk1 ews ] transforms/2d/scale-change-composited.html is a flaky failure

[Karl Rackler]

Description:
transforms/2d/rotate-composited.html 

I have marked this test as skip while this issue is investigated.
https://trac.webkit.org/changeset/268614/webkit