Don't print additional spaces when pretty-printing NoDelim groups

Author: Aaron1011

src/librustc_ast_pretty/pprust.rs

@@ -257,7 +257,7 @@ fn token_kind_to_string_ext(tok: &TokenKind, convert_dollar_crate: Option<Span>)
         token::CloseDelim(token::Bracket) => "]".to_string(),
         token::OpenDelim(token::Brace) => "{".to_string(),
         token::CloseDelim(token::Brace) => "}".to_string(),
-        token::OpenDelim(token::NoDelim) | token::CloseDelim(token::NoDelim) => " ".to_string(),
+        token::OpenDelim(token::NoDelim) | token::CloseDelim(token::NoDelim) => "".to_string(),
         token::Pound => "#".to_string(),
         token::Dollar => "$".to_string(),
         token::Question => "?".to_string(),

src/test/ui/proc-macro/input-interpolated.stdout

@@ -1,5 +1,4 @@
 PRINT-BANG INPUT (DISPLAY): A
-PRINT-BANG RE-COLLECTED (DISPLAY):  A 
 PRINT-BANG INPUT (DEBUG): TokenStream [
     Group {
         delimiter: None,

src/test/ui/proc-macro/nested-macro-rules.stdout

@@ -1,4 +1,4 @@
-PRINT-BANG INPUT (DISPLAY):  FirstStruct 
+PRINT-BANG INPUT (DISPLAY): FirstStruct
 PRINT-BANG INPUT (DEBUG): TokenStream [
     Group {
         delimiter: None,
@@ -12,7 +12,6 @@ PRINT-BANG INPUT (DEBUG): TokenStream [
     },
 ]
 PRINT-BANG INPUT (DISPLAY): SecondStruct
-PRINT-BANG RE-COLLECTED (DISPLAY):  SecondStruct 
 PRINT-BANG INPUT (DEBUG): TokenStream [
     Group {
         delimiter: None,