Support deserialized compilation of the empty program.

pkg/compiler/lib/src/elements/modelx.dart

Index: pkg/compiler/lib/src/elements/modelx.dart
diff --git a/pkg/compiler/lib/src/elements/modelx.dart b/pkg/compiler/lib/src/elements/modelx.dart
index 2e462f4dca7f97f96ff7cc910b4bf3576e9b4060..10c2f71197648518ef2e5fd429b0b53275c055c0 100644
--- a/pkg/compiler/lib/src/elements/modelx.dart
+++ b/pkg/compiler/lib/src/elements/modelx.dart
@@ -3268,7 +3268,15 @@ abstract class AstElementMixin implements AstElement {
   }
 
   ResolvedAst get resolvedAst {
+    Node node = definingElement.node;
+    Node body;
+    if (definingElement.isField) {
+      FieldElement field = definingElement;
+      body = field.initializer;
+    } else if (node != null && node.asFunctionExpression() != null) {
+      body = node.asFunctionExpression().body;
+    }
     return new ParsedResolvedAst(
-        declaration, definingElement.node, definingElement.treeElements);
+        declaration, node, body, definingElement.treeElements);
   }
 }