constructor(localAddress, address, descriptor, rpc) {
    this.localAddress_ = localAddress;
    this.address_ = address;
    this.descriptor_ = descriptor;
    this.rpc_ = rpc;
    this.object_ = null;

    const target = {};
    target[handleSymbol] = this;
    this.proxy_ = new Proxy(target, { get: Handle.proxyHandler_ });
  }
@param {string} localAddress Address of this handle.
@param {string} address Address of the primary handle this handle refers
                to. Primary handle is the one that lives in the same world
                as the actual object it refers to.
@param {!Object} descriptor Target object spec descriptor (list of methods, etc.)
@param {!Rpc} rpc