adjusted signature of removeEventListener to that of addEventListener

Author: aha66

src/main/scala/org/scalajs/dom/raw/lib.scala

@@ -2224,7 +2224,7 @@ class EventTarget extends js.Object {
  *
  * MDN
  */
- def removeEventListener(`type`: String, listener: js.Function1[Event, _], useCapture: Boolean = js.native): Unit = js.native
+ def removeEventListener[T <: Event](`type`: String, listener: js.Function1[T, _], useCapture: Boolean = js.native): Unit = js.native
 
  /**
  * The EventTarget.addEventListener() method registers the specified listener on