Remove fields that are dead since the removal of type ascription syntax

Since `{ ident: ident }` is a parse error, these fields are dead.

Author: fmease

src/closures.rs

@@ -176,7 +176,6 @@ fn rewrite_closure_with_block(
             .first()
             .map(|attr| attr.span.to(body.span))
             .unwrap_or(body.span),
-        could_be_bare_literal: false,
     };
     let block = crate::expr::rewrite_block_with_visitor(
         context,

src/macros.rs

@@ -423,7 +423,6 @@ fn rewrite_empty_macro_def_body(
         rules: ast::BlockCheckMode::Default,
         span,
         tokens: None,
-        could_be_bare_literal: false,
     };
     block.rewrite_result(context, shape)
 }