Fix or suppress upcoming JSCompiler type errors

See https://paste.googleplex.com/6582944531480576 for the original errors being fixed. A JSCompiler change will improve type information in some cases, which uncovers these new errors.

If you've received a CL with suppressions or casts, you are warmly encouraged to properly fix it later on (or if the fix is simple, please suggest an edit).

Tested:
    TAP --sample ran all affected tests and none failed
    http://test/OCL:273653133:BASE:273633972:1570586513373:ab143a07
PiperOrigin-RevId: 273871546
1 file changed