Migrate symbols to use declarative macro.

Author: fee1-dead

compiler/rustc_macros/src/lib.rs

@@ -13,19 +13,13 @@ mod newtype;
 mod query;
 mod serialize;
 mod session_diagnostic;
-mod symbols;
 mod type_foldable;
 
 #[proc_macro]
 pub fn rustc_queries(input: TokenStream) -> TokenStream {
     query::rustc_queries(input)
 }
 
-#[proc_macro]
-pub fn symbols(input: TokenStream) -> TokenStream {
-    symbols::symbols(input.into()).into()
-}
-
 /// Creates a struct type `S` that can be used as an index with
 /// `IndexVec` and so on.
 ///