fix #28008, fix #28009 implement FutureOr<T>

pkg/analyzer/lib/src/summary/resynthesize.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 summary_resynthesizer;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/standard_ast_factory.dart';
@@ skipping 1342 matching lines @@
     return typeArguments;
   }
 }
 
 class _ResynthesizerContext implements ResynthesizerContext {
   final _UnitResynthesizer _unitResynthesizer;
 
   _ResynthesizerContext(this._unitResynthesizer);
 
   @override
+  bool get isStrongMode => _unitResynthesizer.summaryResynthesizer.strongMode;
+
+  @override
   ElementAnnotationImpl buildAnnotation(ElementImpl context, UnlinkedExpr uc) {
     return _unitResynthesizer.buildAnnotation(context, uc);
   }
 
   @override
   Expression buildExpression(ElementImpl context, UnlinkedExpr uc) {
     return _unitResynthesizer._buildConstExpression(context, uc);
   }
 
   @override
@@ skipping 357 matching lines @@
           String identifier = _getElementIdentifier(name, linkedReference.kind);
           locationComponents =
               enclosingInfo.element.location.components.toList();
           locationComponents.add(identifier);
         } else {
           String identifier = _getElementIdentifier(name, linkedReference.kind);
           locationComponents =
               libraryResynthesizer.getReferencedLocationComponents(
                   linkedReference.dependency, linkedReference.unit, identifier);
         }
+        if (!_resynthesizerContext.isStrongMode &&
+            locationComponents.length == 3 &&
+            locationComponents[0] == 'dart:async' &&
+            locationComponents[2] == 'FutureOr') {
+          type = typeProvider.dynamicType;
+          numTypeParameters = 0;
+        }
         ElementLocation location =
             new ElementLocationImpl.con3(locationComponents);
         if (enclosingInfo != null) {
           numTypeParameters += enclosingInfo.numTypeParameters;
         }
         switch (linkedReference.kind) {
           case ReferenceKind.classOrEnum:
             element = new ClassElementHandle(summaryResynthesizer, location);
             break;
           case ReferenceKind.constructor:
@@ skipping 129 matching lines @@
   static String _getElementIdentifier(String name, ReferenceKind kind) {
     if (kind == ReferenceKind.topLevelPropertyAccessor ||
         kind == ReferenceKind.propertyAccessor) {
       if (!name.endsWith('=')) {
         return name + '?';
       }
     }
     return name;
   }
 }