short int might not be large enough to represent all of the values in a wchar_t. Use the integer traits to be sure that we get a type large enough to represent the values of wchar_t

[SVN r63072]

libs/serialization

@@ -1 +1 @@
-Subproject commit a09bd1f83acf0fe81e967b09989e3032de9f16f3
+Subproject commit 0d3a679eddceb8ec31b94cc5adda4b220ef48c22