Resynth the 'final' property of top-level variables.

pkg/analyzer/lib/src/summary/resynthesize.dart

Index: pkg/analyzer/lib/src/summary/resynthesize.dart
diff --git a/pkg/analyzer/lib/src/summary/resynthesize.dart b/pkg/analyzer/lib/src/summary/resynthesize.dart
index 23b103cb3f4d6c44f4390ee411e1e9892b8566e2..5ce66aaa6826322fe0b1404c07e10a401be39733 100644
--- a/pkg/analyzer/lib/src/summary/resynthesize.dart
+++ b/pkg/analyzer/lib/src/summary/resynthesize.dart
@@ -948,6 +948,7 @@ class _LibraryResynthesizer {
       UnlinkedVariable serializedVariable) {
     element.type = buildType(serializedVariable.type);
     element.const3 = serializedVariable.isConst;
+    element.final2 = serializedVariable.isFinal;
     element.hasImplicitType = serializedVariable.hasImplicitType;
     buildDocumentation(element, serializedVariable.documentationComment);
   }