Serialize TreeElements

pkg/compiler/lib/src/compiler.dart

Index: pkg/compiler/lib/src/compiler.dart
diff --git a/pkg/compiler/lib/src/compiler.dart b/pkg/compiler/lib/src/compiler.dart
index 3d03876821b687f7785b322174289f74bd86e975..1b01849c9558a21ac442383036edcd05909a46f6 100644
--- a/pkg/compiler/lib/src/compiler.dart
+++ b/pkg/compiler/lib/src/compiler.dart
@@ -1894,6 +1894,25 @@ class _CompilerResolution implements Resolution {
   }
 
   @override
+  bool hasResolvedAst(Element element) {
+    return element is AstElement &&
+        hasBeenResolved(element) &&
+        element.hasResolvedAst;
+  }
+
+  @override
+  ResolvedAst getResolvedAst(Element element) {
+    if (hasResolvedAst(element)) {
+      AstElement astElement = element;
+      return astElement.resolvedAst;
+    }
+    assert(invariant(element, hasResolvedAst(element),
+        message: "ResolvedAst not available for $element."));
+    return null;
+  }
+
+
+  @override
   bool hasResolutionImpact(Element element) {
     return _resolutionImpactCache.containsKey(element);
   }