Editorial: simplify AsyncGeneratorDrainQueue (#3411)

Author: bakkot

spec.html

@@ -49322,23 +49322,17 @@ <h1>
         <emu-alg>
           1. Assert: _generator_.[[AsyncGeneratorState]] is ~draining-queue~.
           1. Let _queue_ be _generator_.[[AsyncGeneratorQueue]].
-          1. If _queue_ is empty, then
-            1. Set _generator_.[[AsyncGeneratorState]] to ~completed~.
-            1. Return ~unused~.
-          1. Let _done_ be *false*.
-          1. Repeat, while _done_ is *false*,
+          1. Repeat, while _queue_ is not empty,
             1. Let _next_ be the first element of _queue_.
             1. Let _completion_ be Completion(_next_.[[Completion]]).
             1. If _completion_ is a return completion, then
               1. Perform AsyncGeneratorAwaitReturn(_generator_).
-              1. Set _done_ to *true*.
+              1. Return ~unused~.
             1. Else,
               1. If _completion_ is a normal completion, then
                 1. Set _completion_ to NormalCompletion(*undefined*).
               1. Perform AsyncGeneratorCompleteStep(_generator_, _completion_, *true*).
-              1. If _queue_ is empty, then
-                1. Set _generator_.[[AsyncGeneratorState]] to ~completed~.
-                1. Set _done_ to *true*.
+          1. Set _generator_.[[AsyncGeneratorState]] to ~completed~.
           1. Return ~unused~.
         </emu-alg>
       </emu-clause>