Support for AwaitExpression in unlinked expressions.

pkg/analyzer/test/src/summary/resynthesize_common.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library test.src.serialization.elements_test;
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/constant/value.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
@@ skipping 3611 matching lines @@
 int f(int x(String y)) => null;
 String g(int x(String y)) => null;
 var v = [f, g];
 ''');
   }
 
   test_initializer_executable_with_return_type_from_closure() {
     checkLibrary('var v = () => 0;');
   }
 
+  test_initializer_executable_with_return_type_from_closure_await_dynamic() {
+    checkLibrary('var v = (f) async => await f;');
+  }
+
+  test_initializer_executable_with_return_type_from_closure_await_future_int() {
+    checkLibrary(r'''
+import 'dart:async';
+var v = (Future<int> f) async => await f;
+''');
+  }
+
+  test_initializer_executable_with_return_type_from_closure_await_future_noArg() {
+    checkLibrary(r'''
+import 'dart:async';
+var v = (Future f) async => await f;
+''');
+  }
+
   test_initializer_executable_with_return_type_from_closure_field() {
     checkLibrary('''
 class C {
   var v = () => 0;
 }
 ''');
   }
 
   test_initializer_executable_with_return_type_from_closure_local() {
     checkLibrary('''
@@ skipping 1117 matching lines @@
       fail('Unexpectedly tried to get unlinked summary for $uri');
     }
     return serializedUnit;
   }
 
   @override
   bool hasLibrarySummary(String uri) {
     return true;
   }
 }