On the following tests, WebKitTestRunner goes crazy, using more than 100% CPU apparently handling a flood of mach messages: fast/block/basic/min-pref-width-nowrap-floats.html editing/style/5017613-2.html fast/forms/input-appearance-focus.html svg/clip-path/clip-path-on-g.svg tables/mozilla_expected_failures/marvin/table_overflow_style_reflow_row_sibling.html
Created attachment 61634 [details] Sample of WebKitTestRunner Attached a sample of WebKitTestRunner while it is in this spinning state. This is easily reproducible running WebKitTestRunner on one of the tests by hand.
<rdar://problem/8194510>
Created attachment 61691 [details] Patch
Committed r63442: <http://trac.webkit.org/changeset/63442>