Refactor python_android test to separate Android-specific components (#27453)
Summary:
All of the test cases move into a base class that is extended by the
intrumentation test and a new "HostTests" class that can be run in
normal Java. (Some changes to the build script and dependencies are
required before the host test can actually run.)
ghstack-source-id: fe1165b513241b92c5f4a81447f5e184b3bfc75e
Pull Request resolved: https://github.com/pytorch/pytorch/pull/27453
Test Plan: Imported from OSS
Reviewed By: IvanKobzarev
Differential Revision: D17800410
fbshipit-source-id: 1184f0caebdfa219f4ccd1464c67826ac0220181
