Indentation is broken for multiple line comments inside struct

[rhysd]

I'm not sure this is a bug or intended behavior. So if it is intended, please feel free to close this.

Environment

• rustfmt: rustfmt 1.4.11-nightly (18382352 2019-12-03)
• OS: macOS 10.14

Repro

Please prepare following code:

struct X {
    // foo
    // bar
}

and run rustfmt (here I'm using nightly):

$ rustup run nightly rustfmt blah.rs

Expected behavior

rustfmt changes nothing

Actual behavior

rustfmt changes code as follows:

struct X {
    // foo
// bar
}