Update the wording based on feedback.

* Clarified that `event::wait_and_throw` will pass to an async handler
  all unhandled asynchronous errors which are held by a queue or context
  associated with the event and dependent events.
* Added a note that this behaviour is equivalent to calling
  `queue::throw_asynchornous` on each event.
* Clarified that the async handler that is used to process the
  asynchornous errors is determined acording to the async handler
  priorities specified in section 4.13.1.3.

adoc/chapters/programming_interface.adoc

@@ -3835,13 +3835,16 @@ void wait_and_throw()
    a@ Blocks until all commands associated with this event and any dependent
       events have completed.
 
-Any unconsumed <<async-error,asynchronous errors>> which were produced by the
-execution of commands associated with this event or any dependent events, are
-passed to the <<async-handler>> associated with the respective context.
+Any uncomsumed <<async-error,asynchronous errors>> held by queues (or their
+associated contexts) which were used to enqueue commands associated with this
+event and any dependent events, are passed to the approriate <<async-handler>>
+as described in <<async.handler.priorities>>.
 
-If no user defined <<async-handler>> is associated with the context, then an
-implementation-defined default <<async-handler>> is invoked to handle errors,
-as described in <<subsubsec:exception.nohandler>>.
+[NOTE]
+====
+This behaviour is equivalent to calling [code]#queue::throw_asynchronous()# on
+the queue associated with this event and any dependent events.
+====
 
 a@
 [source]
@@ -16458,6 +16461,7 @@ defined in <<subsubsec:exception.async>>.
 The default <<async-handler>> must in some way report all errors passed to it,
 when possible, and must then invoke [code]#std::terminate# or equivalent.
 
+[[subsubsec:async.handler.priorities]]
 ==== Priorities of async handlers
 
 If the SYCL runtime can associate an <<async-error>> with a specific queue,