Editorial: AsyncGeneratorAwaitReturn does not throw (#2683)

spec.html

@@ -48263,7 +48263,7 @@ <h1>%AsyncGeneratorPrototype%.return ( _value_ )</h1>
           1. Let _state_ be _generator_.[[AsyncGeneratorState]].
           1. If _state_ is either ~suspended-start~ or ~completed~, then
             1. Set _generator_.[[AsyncGeneratorState]] to ~awaiting-return~.
-            1. Perform ! AsyncGeneratorAwaitReturn(_generator_).
+            1. Perform AsyncGeneratorAwaitReturn(_generator_).
           1. Else if _state_ is ~suspended-yield~, then
             1. Perform AsyncGeneratorResume(_generator_, _completion_).
           1. Else,
@@ -48552,7 +48552,7 @@ <h1>
         <h1>
           AsyncGeneratorAwaitReturn (
             _generator_: an AsyncGenerator,
-          ): either a normal completion containing ~unused~ or a throw completion
+          ): ~unused~
         </h1>
         <dl class="header">
         </dl>
@@ -48609,7 +48609,7 @@ <h1>
             1. Let _completion_ be Completion(_next_.[[Completion]]).
             1. If _completion_ is a return completion, then
               1. Set _generator_.[[AsyncGeneratorState]] to ~awaiting-return~.
-              1. Perform ! AsyncGeneratorAwaitReturn(_generator_).
+              1. Perform AsyncGeneratorAwaitReturn(_generator_).
               1. Set _done_ to *true*.
             1. Else,
               1. If _completion_ is a normal completion, then