Reference to nested enum broken by recent change

[alexeagle]

in https://github.com/google/closure-library/blob/master/closure/goog/events/wheelevent.js
we see

/**
 * @param {goog.events.WheelEvent.DeltaMode} deltaMode The delta mode units of
 *     the wheel event.
 * @constructor
 */
goog.events.WheelEvent = function(
    browserEvent, deltaMode, deltaX, deltaY, deltaZ) {

We emit

declare namespace ಠ_ಠ.cl2dts_internal.goog.events {
  class WheelEvent extends BrowserEvent {
    constructor (browserEvent : Event , deltaMode : WheelEvent.DeltaMode , deltaX : number , deltaY : number , deltaZ : number ) ;
    deltaMode : WheelEvent.DeltaMode ;
    type : WheelEvent.EventType ;
    static PIXELS_PER_PAGE_ : number ;
    /* not emitting EventType because it is an enum and it is not provided */
    /* not emitting DeltaMode because it is an enum and it is not provided */
    static PIXELS_PER_LINE_ : number ;
  }
}
declare module 'goog:goog.events.WheelEvent' {
  import alias = ಠ_ಠ.cl2dts_internal.goog.events.WheelEvent;
  export default alias;
}

And this is broken because DeltaMode and EventType are omitted and don't appear anywhere else.

Similar to the report in #71 and probably broken by our fix to #69

[mprobst]

I believe this is obsolete, we dropped that code.