user32: Fix returned value of LB_DIR.

dlls/user32/listbox.c

@@ -1815,6 +1815,7 @@ static LRESULT LISTBOX_Directory( LB_DESCR *descr, UINT attrib,
     LRESULT ret = LB_OKAY;
     WIN32_FIND_DATAW entry;
     int pos;
+    LRESULT maxinsert = LB_ERR;
 
     /* don't scan directory if we just want drives exclusively */
     if (attrib != (DDL_DRIVES | DDL_EXCLUSIVE)) {
@@ -1860,13 +1861,17 @@ static LRESULT LISTBOX_Directory( LB_DESCR *descr, UINT attrib,
                 pos = LISTBOX_FindFileStrPos( descr, buffer );
                 if ((ret = LISTBOX_InsertString( descr, pos, buffer )) < 0)
                     break;
+                if (ret <= maxinsert) maxinsert++; else maxinsert = ret;
             } while (FindNextFileW( handle, &entry ));
             FindClose( handle );
         }
     }
+    if (ret >= 0)
+    {
+        ret = maxinsert;
 
         /* scan drives */
-    if ((ret >= 0) && (attrib & DDL_DRIVES))
+        if (attrib & DDL_DRIVES)
         {
             WCHAR buffer[] = {'[','-','a','-',']',0};
             WCHAR root[] = {'A',':','\\',0};
@@ -1878,6 +1883,7 @@ static LRESULT LISTBOX_Directory( LB_DESCR *descr, UINT attrib,
                     break;
             }
         }
+    }
     return ret;
 }