Remove ParamEnv::without_caller_bounds

compiler/rustc_middle/src/ty/mod.rs

@@ -991,12 +991,6 @@ impl<'tcx> ParamEnv<'tcx> {
         ParamEnv { caller_bounds }
     }
 
-    /// Returns this same environment but with no caller bounds.
-    #[inline]
-    pub fn without_caller_bounds(self) -> Self {
-        Self::new(ListWithCachedTypeInfo::empty())
-    }
-
     /// Creates a pair of param-env and value for use in queries.
     pub fn and<T: TypeVisitable<TyCtxt<'tcx>>>(self, value: T) -> ParamEnvAnd<'tcx, T> {
         ParamEnvAnd { param_env: self, value }