Currently, the font matching algorithm operates on individual values, when it should operate on ranges.
https://bugs.webkit.org/show_bug.cgi?id=168678 creates the infrastructure for this, but the variation ranges from Core Text need to be consulted.
Created attachment 303591 [details]
Attachment 303591 [details] did not pass style-queue:
ERROR: Source/WebCore/ChangeLog:8: You should remove the 'No new tests' and either add and list tests, or explain why no new tests were possible. [changelog/nonewtests] 
Total errors found: 1 in 2 files
If any of these errors are false positives, please file a bug against check-webkit-style.
Will be done in https://bugs.webkit.org/show_bug.cgi?id=168893
*** This bug has been marked as a duplicate of bug 168893 ***