[javascriptcore-test262-automation] Changes from https://github.com/webkit/webkit.git at sha f1aff87cc3 on Wed Oct 03 2018 18:33:02 GMT+0000 (Coordinated Universal Time)

Remove more stress tests with existing coverage or out of context for test262

[javascriptcore-test262-automation] Changes from https://github.com/webkit/webkit.git at sha ffc7368147 on Tue Aug 21 2018 18:14:08 GMT+0000 (Coordinated Universal Time)