[scope] Null out rare_data_ when aborting preparsing

When we abort preparsing, we have to reset the Scope state, to ensure
re-parsing will leave us in the proper Zone. Resetting of rare_data_
was missing, causing this to fail in some cases.

Bug: chromium:740803
Change-Id: I7ce70f9c4670eaf1b76745ae8231eb95625b0f4b
Reviewed-on: https://chromium-review.googlesource.com/568784Reviewed-by: Caitlin Potter <caitp@igalia.com>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46607}

src/ast/scopes.cc

@@ -1492,6 +1492,7 @@ void DeclarationScope::ResetAfterPreparsing(AstValueFactory* ast_value_factory,
   inner_scope_ = nullptr;
   unresolved_ = nullptr;
   sloppy_block_function_map_ = nullptr;
+  rare_data_ = nullptr;
 
   if (aborted) {
     // Prepare scope for use in the outer zone.

test/mjsunit/regress/regress-crbug-740803.js

+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+({
+   m() {
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x; x;
+     x;
+   }
+})