Support transitive dependencies through android_libary_import modules

Fix dependencies of android_library_import modules so that the -nodeps
modules created by pom2bp are no longer necessary.  Provide transitive
manifests (b/288358614), combine static dependencies into the output
jars, and propagate uses_libraries and optional_uses_libraries from
dependencies.

Bug: 288358614
Test: TestManifestMerger
Test: TestAndroidResourceProcessor
Change-Id: Ief45169d04217826fbb21ba283602b38ef0dd3f6