[PushStream] PushStream#onError has Documentation of onClose

[bjhargrave]

Original bug ID: BZ#3107
From: @juergen-albert
Reported version: R7

[bjhargrave]

Comment author: @juergen-albert

I guess there should be a difference. It currently looks like a copy&waste mistake.

/**
* Must be run after the channel is closed. This handler will run after the
* downstream methods have processed the close event and before the upstream
* methods have closed.
*
* @ param closeHandler Will be called on close
* @ return This stream
*/
PushStream onClose(Runnable closeHandler);

/**
 * Must be run after the channel is closed. This handler will run after the
 * downstream methods have processed the close event and before the upstream
 * methods have closed.
 * 
 * @ param closeHandler Will be called on close
 * @ return This stream
 */
PushStream<T> onError(Consumer< ? super Throwable> closeHandler);