LWG4027 possibly-const-range should prefer returning const R&

Author: burblebee

source/ranges.tex

@@ -396,7 +396,7 @@
   // \ref{range.as.const}, as const view
   template<@\libconcept{input_range}@ R>
     constexpr auto& @\exposid{possibly-const-range}@(R& r) noexcept { // \expos
-      if constexpr (@\libconcept{constant_range}@<const R> && !@\libconcept{constant_range}@<R>) {
+      if constexpr (@\libconcept{input_range}@<const R>) {
         return const_cast<const R&>(r);
       } else {
         return r;