The layout test editing/pasteboard/img-srcset-copy-paste-canonicalization.html fails on platform GTK since it was added on r171941 <http://trac.webkit.org/r171941> The diff is the following: http://build.webkit.org/results/GTK%20Linux%2064-bit%20Release%20%28Tests%29/r171943%20%281846%29/editing/pasteboard/img-srcset-copy-paste-canonicalization-pretty-diff.html HighDPI support is not enabled on platform GTK (bug 131347) Could be the failure related with that?
Updated the GTK TestExpectations on http://trac.webkit.org/changeset/171963 for this failure