Fix fatal bug in ArgsArray(wchar_t**) ctor.

The input pointer was modified before being used again leading to out of bound
array access.

Closes #11979.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@64098 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/unix/utilsunx.cpp

@@ -394,7 +394,7 @@ public:
     ArgsArray(wchar_t **wargv)
     {
         int argc = 0;
-        while ( *wargv++ )
+        while ( wargv[argc] )
             argc++;
 
         Init(argc);