Remove the global list of vendor public library modules used to rewrite
dependencies from the vendor module to the stubs for system modules,
and replace it with building the stubs directly in the system variant
of the vendor module.
Bug: 178231622
Test: vendor_public_library_test.go
Change-Id: I826e69ffd507d7e85fa3d4d85b5157428c642143
Vendor public libraries are checked for product modules, but never
reached because the VNDK check occurs first, and wouldn't work anyways
because vendor_public_library did not have the product_available
property. Reorder the rewrite checks and add VendorProperties, and
add a test.
Bug: 178231622
Test: vendor_public_library_test.go
Change-Id: Idbd2802fbd134d22c30600762cb0465633703506