Using `include_dependency` with a non-existent file triggers precompilation at every startup

[longqian95]

found this issue after v1.9. no problems at v1.4

[vchuravy]

include_dependency should probably error if the file doesn't exist.

[KristofferC]

Unless you want to recompile something if a file start to existing I guess... But that feels like kind of strange use case. Anyway, at least it shouldn't recompile if the file continues to not exist.