Codechange: make StringParameters#next_type only writable from outside the class

src/strings.cpp

@@ -899,7 +899,7 @@ static void FormatString(StringBuilder &builder, const char *str_arg, StringPara
 			continue;
 		}
 
-		args.next_type = b;
+		args.SetTypeOfNextParameter(b);
 		switch (b) {
 			case SCC_ENCODED: {
 				uint64 sub_args_data[20];

src/strings_internal.h

@@ -19,10 +19,11 @@ protected:
 	uint64 *data;             ///< Array with the actual data.
 	WChar *type;              ///< Array with type information about the data. Can be nullptr when no type information is needed. See #StringControlCode.
 
+	WChar next_type = 0; ///< The type of the next data that is retrieved.
+
 public:
 	size_t offset = 0; ///< Current offset in the data/type arrays.
 	size_t num_param; ///< Length of the data array.
-	WChar next_type = 0; ///< The type of the next data that is retrieved.
 
 	/** Create a new StringParameters instance. */
 	StringParameters(uint64 *data, size_t num_param, WChar *type) :
@@ -57,6 +58,7 @@ public:
 	}
 
 	void ClearTypeInformation();
+	void SetTypeOfNextParameter(WChar type) { this->next_type = type; }
 
 	int64 GetInt64();