apilint: Lint unhidden @IntDef and @LongDef

@IntDefs and @LongDefs cannot be stored in a .class file, because the constant
names are lost. Instead, they are packaged out-of-band.

Therefore, they should never be in the API.

Test: python tools/apilint/apilint.py api/current.txt
Change-Id: If22e0cf7db0bb90dae6174bf546f2ec8be4e5458