Make sure MediaRecorder does not call fetchData until the last fetchData is completed
Created attachment 410417 [details] Patch
Created attachment 410419 [details] Patch
<rdar://problem/69910406>
Created attachment 410422 [details] Patch
Created attachment 410425 [details] Patch
Committed r267941: <https://trac.webkit.org/changeset/267941> All reviewed patches have been landed. Closing bug and clearing flags on attachment 410425 [details].