Remove app preference from ANGLE logic

* The use of meta-data to specify app preference for ANGLE was
  temporary, so remove it.
* Since we no longer plan to allow apps to specify a preference
  at all, remove the JNI plumbing.

Bug: 80239516
Test: Manual build, ensure rules are followed
Test: cts-tradefed run singleCommand cts -m CtsAngleIntegrationHostTestCases
Change-Id: If8eb6087ae85bb82eae6625778e1c3a926fe038a