hpb: Disambiguate betwixt mutable and agnostic PtrOrRaw (mutable or const)

PiperOrigin-RevId: 704738982

hpb/backend/upb/upb.h

@@ -9,14 +9,13 @@
 #define GOOGLE_PROTOBUF_HPB_BACKEND_UPB_UPB_H__
 
 #include "google/protobuf/hpb/backend/upb/interop.h"
-#include "google/protobuf/hpb/internal/internal.h"
 #include "google/protobuf/hpb/internal/template_help.h"
 #include "google/protobuf/hpb/ptr.h"
 
 namespace hpb::internal::backend::upb {
 
 template <typename T>
-void ClearMessage(hpb::internal::PtrOrRaw<T> message) {
+void ClearMessage(hpb::internal::PtrOrRawMutable<T> message) {
   auto ptr = Ptr(message);
   auto minitable = hpb::interop::upb::GetMiniTable(ptr);
   upb_Message_Clear(hpb::interop::upb::GetMessage(ptr), minitable);

hpb/hpb.h

@@ -79,7 +79,7 @@ void DeepCopy(const T* source_message, T* target_message) {
 }
 
 template <typename T>
-void ClearMessage(hpb::internal::PtrOrRaw<T> message) {
+void ClearMessage(hpb::internal::PtrOrRawMutable<T> message) {
   backend::ClearMessage(message);
 }
 

hpb/internal/template_help.h

@@ -33,6 +33,9 @@ using RemovePtrT = typename RemovePtr<T>::type;
 
 template <typename T, typename U = RemovePtrT<T>,
           typename = std::enable_if_t<!std::is_const_v<U>>>
+using PtrOrRawMutable = T;
+
+template <typename T, typename U = RemovePtrT<T>>
 using PtrOrRaw = T;
 
 template <typename T, typename = void>