This regresses the test case of `zig fmt` deleting empty line comments.
Two open questions here:
* What should the rules be about deleting empty line comments?
It makes sense usually, but for array initization, empty line
comments cause a line break, affecting the row/column alignment.
Perhaps we should therefore respect all empty line comments?
Or should we special case array initializations?
* If we decide to special case some kinds of line comments to respect
them (which is status quo!), how should that be implemented?
1e3a200ba6