`include_bytes!` should add file dependencies like `include_str!`

[huonw]

This causes cargo to misbehave: rust-lang/cargo#1510

Tagging as E-easy, since @tomaka has tracked down the appropriate fix.

[tbelaire]

I'm going to try and fix this.

[tbelaire]

After reading the files libsyntax/ext/source_util.rs and libsyntax/coremap.rs, I have come up with a plan.
This is a little bit tricky, since with include_str!, we know that we are including utf-8 content, so it's safe to store the source as a String in a FileMap. We don't know that for include_bytes!, but I don't think we actually need to track the contents anyways, so I'm passing "" to new_filemap.
Currently building, I'll see if that fixes it.

[tamird]

This should have been closed by #24423. Can someone with power close?

[alexcrichton]

Indeed!