Apply coding conventions

test/printf-test.cc

@@ -310,10 +310,10 @@ TEST(printf_test, dynamic_precision) {
   }
 }
 
-template <typename T> struct make_signed { typedef T type; };
+template <typename T> struct make_signed { using type = T; };
 
 #define SPECIALIZE_MAKE_SIGNED(T, S) \
-  template <> struct make_signed<T> { typedef S type; }
+  template <> struct make_signed<T> { using type = S; }
 
 SPECIALIZE_MAKE_SIGNED(char, signed char);
 SPECIALIZE_MAKE_SIGNED(unsigned char, signed char);