MODULES: lib1, main

STEP 0:
    libs: lib1, main
    dirty js modules: lib1, main
    dirty js files:   lib1/l1, main/m, main/m.export
STEP 1..6:
    libs: lib1, main
    dirty js modules: lib1, main
    dirty js files:   lib1/l1, main/m
STEP 7..8:
    libs: lib1, main
    dirty js modules: lib1, main
    dirty js files:   lib1/l1, main/m
STEP 9..16:
    libs: lib1, main
    dirty js modules: lib1, main
    dirty js files:   lib1/l1, main/m