Store FunctionType(s) of local functions by value.

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 66f6878c3074c8ebecc19345331624cf5d4ef60f..f6855dbc12ca0fa3c6a38b5a47c9795b5e830dc3 100644
--- a/pkg/analyzer/lib/src/summary/resynthesize.dart
+++ b/pkg/analyzer/lib/src/summary/resynthesize.dart
@@ -1655,7 +1655,7 @@ class _UnitResynthesizer {
       GenericFunctionTypeElement element =
           new GenericFunctionTypeElementImpl.forSerialized(context, type);
       return element.type;
-    } else if (type.syntheticReturnType != null) {
+    } else if (type.syntheticReturnType != null && type.reference == 0) {
       FunctionElementImpl element =
           new FunctionElementImpl_forLUB(context, type);
       return element.type;