**Do you want to request a *feature* or report a *bug*?**
bug

**What is the current behavior?**
In normal rendering, you can memoize a class-based component: https://jsfiddle.net/586ea3cx/

With the shallow renderer, it seems like you can't: https://jsfiddle.net/odj217Lv/1/

This might be blocking https://github.com/airbnb/enzyme/pull/1914, in which tests are failing with `Cannot call a class as a function`. (it's tough to repro stuff with the shallow renderer)
(this._currentlyRenderingComponent: any),
          queue,
        ): any));
        return [workInProgressHook.memoizedState, dispatch];
      }
    };
    const useState = <S>(
      initialState: (() => S) | S,
    ): [S, Dispatch<BasicStateAction<S>>] => {
      return useReducer(
        basicStateReducer,
        
        (initialState: any),
      );
    };
    const useMemo = <T>(
      nextCreate: () => T,
      deps: Array<mixed> | void | null,
    ): T => {
      this._validateCurrentlyRenderingComponent();
      this._createWorkInProgressHook();
      const nextDeps = deps !== undefined ? deps : null;
      if (
        this._workInProgressHook !== null &&
        this._workInProgressHook.memoizedState !== null
      ) {
        const prevState = this._workInProgressHook.memoizedState;
        const prevDeps = prevState[1];
        if (nextDeps !== null) {
          if (areHookInputsEqual(nextDeps, prevDeps)) {