Replaces state ops with non state Placeholder ops for the apply graph.

def replace_apply_state(meta_graph, state_ops, feed_map):
  """Replaces state ops with non state Placeholder ops for the apply graph."""
  for node in meta_graph.graph_def.node:
    keys_to_purge = []
    tensor_name = node.name + ":0"
    # Verify that the node is a state op and that its due to be rewired
    # in the feedmap.
    if node.op in state_ops and tensor_name in feed_map:
      node.op = "Placeholder"
      for key in node.attr:
        # Only shape and dtype are required for Placeholder. Remove other
        # attributes.
        if key != "shape":
          keys_to_purge.append(key)
      for key in keys_to_purge:
        del node.attr[key]
      node.attr["dtype"].type = types_pb2.DT_RESOURCE