fast/text/han-generic-font-families.html, which was added in r186001, always fails on Yosemite bots.
It appears that an unexpected font is being used in DumpRenderTree and WebKitTestRunner as loading the two test cases in Safari on bot192 works as expected (the images match):
In other words, 'Heiti SC' and 'Heiti TC' are not being used to render the last two lines of the test.
The 'Songti SC' and 'Songti TC' fonts are being used as expected.
Marked test as failing in r186027: <http://trac.webkit.org/r186027>
Looking into this today.
(In reply to comment #2)
> Marked test as failing in r186027: <http://trac.webkit.org/r186027>
Created attachment 255706 [details]
Committed r186034: <http://trac.webkit.org/changeset/186034>