This test introduced in http://trac.webkit.org/changeset/107000 and fails on Qt: http://build.webkit.sed.hu/results/x86-64%20Linux%20Qt%20Release/r107052%20%2833436%29/fast/text/international/inline-plaintext-is-isolated-diffs.html
I think this fail (maybe) was caused by missing utf8 in our testfonts.
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