Expand ResolvedAst to handle synthetic constructors.

pkg/compiler/lib/src/serialization/element_serialization.dart

Index: pkg/compiler/lib/src/serialization/element_serialization.dart
diff --git a/pkg/compiler/lib/src/serialization/element_serialization.dart b/pkg/compiler/lib/src/serialization/element_serialization.dart
index 78228ca41395b8220d86395e999bb1b84fa97a54..0aab229c9cdd533f3da5dd34d40fe93bb6d65106 100644
--- a/pkg/compiler/lib/src/serialization/element_serialization.dart
+++ b/pkg/compiler/lib/src/serialization/element_serialization.dart
@@ -105,7 +105,7 @@ class SerializerUtil {
     if (element.sourcePosition != null) {
       SourceSpan position = element.sourcePosition;
       encoder.setInt(Key.OFFSET, position.begin);
-      if (position.uri != element.compilationUnit.script.resourceUri) {
+      /*if (position.uri != element.compilationUnit.script.resourceUri)*/ {
         // TODO(johnniwinther): What is the base URI in the case?
         encoder.setUri(Key.URI, element.library.canonicalUri, position.uri);
       }