transitive r8 flags for installable {android,java}_libraries

Only android_apps were actually applying transitive proguard flags files
to their r8 invocation. This CL ensures that this also occurs for
installable android_libraries and java_libraries.

Bug: 302342049
Test: go test ./java
Change-Id: Ie94d688d04367ee3d39e7e760fb3003df5829951