This is bug 131839 for Windows.
Created attachment 263839 [details]
Created attachment 263847 [details]
Attachment 263847 [details] did not pass style-queue:
ERROR: Source/WebCore/platform/graphics/win/SimpleFontDataCGWin.cpp:70: Missing spaces around / [whitespace/operators] 
Total errors found: 1 in 5 files
If any of these errors are false positives, please file a bug against check-webkit-style.
Comment on attachment 263847 [details]
Just asking a first review to get some feedback...
The patch has *not* been verified on a Windows machine.
The style error is bug 150396 and it seems that we can not workaround that because kCTFontTableOS2 is not defined on Windows. Maybe this requires an additional header but I can't find a public documentation for Windows.
It's a shame that the CGFont API does not have a more straightforward way to access the typo metrics. For SimpleFontDataCGWin, I just copied & adapted what was done for Mac in bug 150396. I'm afraid the same will be necessary for iOS...
As said in bug 150394 comment 13, I can add more code to restrict this change to font with a MATH table if that's desired. Again, the CGFont API does not seem to have a simple & fast way to verify whether a MATH table is present, so in bug 150394 I just adapted the fontHasVerticalGlyphs function from FontCocoa.mm.
Created attachment 263857 [details]
testcase (requires Cambria Math)
Committed r191893: <http://trac.webkit.org/changeset/191893>