[wasm] Throw PlatformNotSupportedException instead of NotSupportedExc…

…eption when starting threads/waiting on monitors. (#37604)

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Co-authored-by: vargaz <vargaz@users.noreply.github.com>

src/mono/mono/metadata/monitor.c

@@ -1412,7 +1412,7 @@ mono_monitor_wait (MonoObjectHandle obj_handle, guint32 ms, MonoBoolean allow_in
 
 #ifdef DISABLE_THREADS
 	if (ms == MONO_INFINITE_WAIT) {
-		mono_error_set_synchronization_lock (error, "Cannot wait on monitors on this runtime.");
+		mono_error_set_platform_not_supported (error, "Cannot wait on monitors on this runtime.");
 		return FALSE;
 	}
 #endif

src/mono/mono/metadata/threads.c

@@ -1710,7 +1710,7 @@ ves_icall_System_Threading_Thread_Thread_internal (MonoThreadObjectHandle thread
 	MonoObject *start = MONO_HANDLE_RAW (start_handle);
 
 #ifdef DISABLE_THREADS
-	mono_error_set_not_supported (error, "Cannot start threads on this runtime.");
+	mono_error_set_platform_not_supported (error, "Cannot start threads on this runtime.");
 	return FALSE;
 #endif
 
@@ -6744,7 +6744,7 @@ ves_icall_System_Threading_Thread_StartInternal (MonoThreadObjectHandle thread_h
 	gboolean res;
 
 #ifdef DISABLE_THREADS
-	mono_error_set_not_supported (error, "Cannot start threads on this runtime.");
+	mono_error_set_platform_not_supported (error, "Cannot start threads on this runtime.");
 	return;
 #endif
 

src/mono/mono/utils/mono-error-internals.h

@@ -278,6 +278,11 @@ mono_error_set_cannot_unload_appdomain (MonoError *error, const char *message)
 	mono_error_set_generic_error (error, "System", "CannotUnloadAppDomainException", "%s", message);
 }
 
+static inline void
+mono_error_set_platform_not_supported (MonoError *error, const char *message)
+{
+	mono_error_set_generic_error (error, "System", "PlatformNotSupportedException", "%s", message);
+}
 
 MonoException*
 mono_error_prepare_exception (MonoError *error, MonoError *error_out);