Fix Resolution.getResolvedAst for serialization in production mode

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 bdda974edd1af72131f9b7c3c4152528c9e001e4..762e315d9979c2145465fa688ea0e7e136e5318d 100644
--- a/pkg/compiler/lib/src/compiler.dart
+++ b/pkg/compiler/lib/src/compiler.dart
@@ -1992,6 +1992,9 @@ class _CompilerResolution implements Resolution {
         message: "Element $element must be the declaration."));
     assert(invariant(element, hasResolvedAst(element),
         message: "ResolvedAst not available for $element."));
+    if (compiler.serialization.isDeserialized(element)) {
+      return compiler.serialization.getResolvedAst(element);
+    }
     return element.resolvedAst;
   }