After r80892 there are over 100,000 leaks reported on the leaks bot. Prior to that revision the number was much, much smaller.
The reason for this is that r80892 adds duplicate static function entries to the JSClassDefinition in DumpRenderTree’s LayoutTestController.cpp. This appears to cause JavaScriptCore to leak each of the duplicates. This is triggered every time the window object is cleared (once per frame per test?).
Created attachment 85668 [details] Patch The explicit calls to StringImpl::ref seem as though they will also result in leaks as there are no matching calls to StringImpl::deref anywhere. The patch removes those as well as fixing the bigger issue of the leaked duplicate entries.
Fixed in r81051.