On platform GTK the following tests are flaky:
fast/multicol/scrolling-overflow.html [ Failure Pass ]
fast/multicol/span/span-as-immediate-child-generated-content.html [ Failure Pass ]
The results for this two tests were rebaselined on r168097 <http://trac.webkit.org/changeset/168097> after the new multi-column mode was enabled.
However, after the rebaseline, this two tests now are flaky. So I also marked them as such on r168097.
So perhaps there is something wrong with the new multi-column mode on GTK that causes this.
This test(s) has been consistenly failing for the last 4000 revisions, that means the test(s) is no flaky anymore. The test(s) has been gardened and its baseline updated in r269363. Closing bug.