MODULES: lib1, lib2, main

STEP 0:
    libs: lib1, lib2, main
    dirty js: lib1, lib2, main
STEP 1..4:
    libs: lib1, lib2, main
    dirty js: lib1, lib2
STEP 5:
    libs: lib1, lib2, main
    dirty js: lib1, main
STEP 6:
    libs: lib1, lib2, main
    dirty js: lib1, lib2, main