Do not derive source from binary APK

When loading the binary APK, do not set the paths of Source structs to
the path of the binary APK. This causes the merge_zips step of the build
system to fail.

Bug: 124082573
Test: vendor/google/build/build_mainline_modules.sh
Change-Id: I84b8d43c5b6a5835e7ff6bd579c4eb744e02c20f