Fix overlaying android resources from static libraries

Match the make logic for combining app resources with static library
resources.

Bug: 112822358
Test: app_test.go
Test: aapt2 dump resources $OUT/system/priv-app/SystemUIGoogle/SystemUIGoogle.apk | grep -A1 ' string/config_systemUIVendorServiceComponent'
Change-Id: I565404e7ffb726dab952c72ab23600d6f2ee4ad4