Test hh specifier with unsigned char.

test/printf-test.cc

@@ -347,7 +347,7 @@ TEST(PrintfTest, Length) {
   EXPECT_EQ("-1", sprintf_int<unsigned char>("%hhd", UCHAR_MAX));
   EXPECT_EQ("255", sprintf_int<unsigned char>("%hhu", UCHAR_MAX));
   TestLength<signed char>("hh");
-  //TestLength<unsigned char>("hh");
+  TestLength<unsigned char>("hh");
   //TestLength<short>("h");
   //TestLength<unsigned short>("h");
   //TestLength<long>("l");