Implement APEX JAR (Java library) absence checks for Core Libraries.

Refactor existing native library checks to share common logics.

Test: Check that `m installclean && m systemimage` succeeds
Test: Check that `m installclean && m libart && m systemimage` fails
Test: Check that `m installclean && m core-oj && m systemimage` fails
Test: Check that `m installclean && m conscrypt && m systemimage` fails
Test: Check that `m installclean && m libart core-oj conscrypt && m systemimage` fails
Test: Check that
        `export OVERRIDE_TARGET_FLATTEN_APEX=true \
         && m installclean \
         && m systemimage`
      succeeds
Bug: 142944799
Bug: 128708192
Bug: 113374338
Change-Id: I703a837c6bb138af73eeb95fc08e1a87af2d8ad7