Disable validations for full api surface stub java_api_library

java_api_library modules run validation to check the sanity of the API
text files by default when generating the stubs from txt files. However,
this leads to circular dependency issue when the validations are added
to the full api surface stub java_api_library modules as droidstubs may
set sdk_version property. Therefore, disable the validation for full api
surface java_api_library (e.g. android_*_stubs_current) modules.

Test: m nothing --build-from-text-stub
Bug: 288624417
Change-Id: Ib1b7b804736ef4e4cd2ea979aabea211af1927af