shell32: try to guess the working directory in the run dialog

[Juan Lang]

Hi Vincent,

+    while (*src)
+    {
+        *dest = *src;
+        if (*src == '\\')
+        {
+            DWORD attrs = GetFileAttributesW(result);

It sure looks like you're calling GetFileAttributesW with a
non-NULL-terminated string.  I doubt this will work as you intend.
--Juan