AndroidMkEntries now returns multiple AndroidMkEntires so that a module
can emit multiple Make modules if needed.
Bug: 128708192
Test: m
Change-Id: I56b6f76d22943b80329951c5acb80a1b932441ad
apex.go is too big. Separate the build rule and android.mk generation
logic into builder.go and androidmk.go, respectively. prebuilt_apex is
moved to prebuilt.go as well.
No refactoring has been made other than the splitting.
Test: m
Change-Id: I839ab0a1ba2b70ce82d98ac1fa8e3534808b5fd3