Bug 683802 - Force allocation for sized PWSTRINGs in XPCWrappedNative argument conversion. r=mrbkap

This is the last remaining place where we might pass a non-dipper with useAllocator==false to XPCConvert *and, as a consequence*, do something different within XPCConvert. This paves the way for the elimination of useAllocator for non-dipper types.

js/src/xpconnect/src/xpcwrappednative.cpp

@@ -2991,7 +2991,8 @@ CallMethodHelper::ConvertDependentParams()
 
             if((datum_type.IsPointer() &&
                 (datum_type.TagPart() == nsXPTType::T_IID ||
-                 datum_type.TagPart() == nsXPTType::T_PSTRING_SIZE_IS)) ||
+                 datum_type.TagPart() == nsXPTType::T_PSTRING_SIZE_IS) ||
+                 datum_type.TagPart() == nsXPTType::T_PWSTRING_SIZE_IS) ||
                (isArray && datum_type.TagPart() == nsXPTType::T_CHAR_STR))
             {
                 useAllocator = JS_TRUE;