Prepare for decoupling analyzer ASTs from element model.

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

Index: pkg/analyzer/test/src/summary/resynthesize_common.dart
diff --git a/pkg/analyzer/test/src/summary/resynthesize_common.dart b/pkg/analyzer/test/src/summary/resynthesize_common.dart
index ddff695e4bc54cad046edeb511220d73572b5882..5a9cb92430098beee0406c5ffc0c627bbb8868af 100644
--- a/pkg/analyzer/test/src/summary/resynthesize_common.dart
+++ b/pkg/analyzer/test/src/summary/resynthesize_common.dart
@@ -5,6 +5,7 @@
 library test.src.serialization.elements_test;
 
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/standard_resolution_map.dart';
 import 'package:analyzer/dart/constant/value.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
@@ -393,8 +394,9 @@ abstract class AbstractResynthesizeTest extends AbstractSingleUnitTest {
         // In 'class C {static const a = 0; static const b = a;}' the reference
         // to 'a' in 'b' is serialized as a fully qualified 'C.a' reference.
         if (r.prefix.staticElement is ClassElement) {
+          Element oElement = resolutionMap.staticElementForIdentifier(o);
           compareElements(
-              r.prefix.staticElement, o.staticElement?.enclosingElement, desc);
+              r.prefix.staticElement, oElement?.enclosingElement, desc);
           compareConstAsts(r.identifier, o, desc);
         } else {
           fail('Prefix of type ${r.prefix.staticElement.runtimeType} should not'