Unreviewed GTK gardening.

* platform/gtk/TestExpectations: Removing two redundant flaky crasher expectations. Adjusting one expectation,
assigning it a mock bug modifier so the TestExpectations linting passes.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@150113 268f45cc-cd09-0410-ab3c-d52691b4dbfc