Track async causal stack traces

tests/language/vm/async_await_catch_stacktrace_test.dart

Index: tests/language/vm/async_await_catch_stacktrace_test.dart
diff --git a/tests/language/vm/async_await_catch_stacktrace_test.dart b/tests/language/vm/async_await_catch_stacktrace_test.dart
index f49ce1551367ae37277bda07b4ce2a1bb762cdef..727b24232b26a86f88a3a29b97f479cef285c148 100644
--- a/tests/language/vm/async_await_catch_stacktrace_test.dart
+++ b/tests/language/vm/async_await_catch_stacktrace_test.dart
@@ -43,7 +43,6 @@ void main() {
 
       Expect.isFalse(stText.contains("propagateToListeners"));
       Expect.isFalse(stText.contains("_completeError"));
-      Expect.isFalse(stText.contains("main"));
     }
     print("Ending!");
   }