[JSTests] add "extraOptions" run command to support per-test runtime flags
Created attachment 289282 [details] Patch
This bit was originally used in https://bugs.webkit.org/show_bug.cgi?id=161409, but since deciding to use a compile-time flag, it stopped being useful there. But, I think it could still be a useful option to have test coverage in JS features that are hidden behind runtime flags.
Comment on attachment 289282 [details] Patch Please use runMiscNoCJIT if possible.