- The body of a async function should be executed in a Future.mircotask.

runtime/vm/parser.cc

Index: runtime/vm/parser.cc
===================================================================
--- runtime/vm/parser.cc	(revision 42059)
+++ runtime/vm/parser.cc	(working copy)
@@ -6112,7 +6112,7 @@
       Class::ZoneHandle(I, I->object_store()->future_class());
   ASSERT(!future.IsNull());
   const Function& constructor = Function::ZoneHandle(I,
-      future.LookupFunction(Symbols::FutureConstructor()));
+      future.LookupFunction(Symbols::FutureMicrotask()));
   ASSERT(!constructor.IsNull());
   const Class& completer =
       Class::ZoneHandle(I, I->object_store()->completer_class());