Summary:
Changelog: [Internal]

Generated with:

```
python3 codemod.py -d xplat/js --extensions=sh 'THIS_DIR=\$\(cd -P "\$\(dirname "\$\(readlink "\${BASH_SOURCE\[0\]}"' 'THIS_DIR=$(cd -P "$(dirname "$(realpath "${BASH_SOURCE[0]}"'```

Reviewed By: motiz88

Differential Revision: D34379955

fbshipit-source-id: c60521cd6508b203f48ca8c890c450319991c2d4