message: Fix bug in WhileLoopContext.
diff: @@ -2734,7 +2734,7 @@ class WhileContext(ControlFlowContext):
  if shape is not None:
  xs.append(shape)
  for x in xs:
  - inp_op = x.op.inputs[0]
  + inp_op = x.op.inputs[0].op
  control_inputs = graph._control_dependencies_for_inputs([inp_op])
  outer_control_inputs = [op for op in control_inputs
  if self._IsInOuterContext(op)]
  