<rdar://problem/15936507>

PyTuple_SetItem steals a reference to the item it inserts in the tuple
This, plus the Py_XDECREF of the tuple a few lines below, causes our session dictionary to go away after the first time a SWIG layer function is called - with disastrous effects for the first subsequent attempt to use any functionality in ScriptInterpreterPython
This fixes it

llvm-svn: 200429

lldb/scripts/Python/python-wrapper.swig

@@ -135,6 +135,7 @@ public:
         {
             if (!arg)
                 return retval;
+            Py_INCREF(arg); // _SetItem steals a reference
             PyTuple_SetItem(pargs,idx,arg);
             idx++;
         }