I would like to enable this to reduce the gardening need for Qt. This will be extremely useful for pixel tests.
Created attachment 166445 [details] Patch
This patch require rebaselining both the text and pixel dump of tests with scrollbar. The text differs because the mock scrollbar is less thick than the default (on linux) with one single pixel.
Comment on attachment 166445 [details] Patch r=me, but CQ-, we will land it with rebaselining.
Comment on attachment 166445 [details] Patch Landed in https://trac.webkit.org/changeset/130283
Rebaseing patch landed in https://trac.webkit.org/changeset/130286