[parser] Refactor bookmark in SkipLazyFunctionBody

src/parsing/parser.h

Index: src/parsing/parser.h
diff --git a/src/parsing/parser.h b/src/parsing/parser.h
index afd490cbe4612a88e758fccda71d01e6e9926018..fb04c3528fa07e64f18002659cd55da703953956 100644
--- a/src/parsing/parser.h
+++ b/src/parsing/parser.h
@@ -544,15 +544,14 @@ class Parser : public ParserBase<Parser> {
   // Skip over a lazy function, either using cached data if we have it, or
   // by parsing the function with PreParser. Consumes the ending }.
   //
-  // If bookmark is set, the (pre-)parser may decide to abort skipping
+  // If may_abort == true, the (pre-)parser may decide to abort skipping
   // in order to force the function to be eagerly parsed, after all.

[adamk, 2016/08/30 22:13:14]

Mention when it'll return true vs false? I was surprised to see that "true"
means aborted and "false" means "not aborted".

Having read through the code I'm wondering if we'd be better off with an enum
(or maybe a pair of enums) here. It's a bit strange to see the unusual case as
"true".

[nickie, 2016/08/31 13:23:36]

Done.

-  // In this case, it'll reset the scanner using the bookmark.
-  void SkipLazyFunctionBody(int* materialized_literal_count,
-                            int* expected_property_count, bool* ok,
-                            Scanner::BookmarkScope* bookmark = nullptr);
+  bool SkipLazyFunctionBody(int* materialized_literal_count,
+                            int* expected_property_count, bool may_abort,
+                            bool* ok);
 
   PreParser::PreParseResult ParseLazyFunctionBodyWithPreParser(
-      SingletonLogger* logger, Scanner::BookmarkScope* bookmark = nullptr);
+      SingletonLogger* logger, bool may_abort);
 
   Block* BuildParameterInitializationBlock(
       const ParserFormalParameters& parameters, bool* ok);
@@ -878,6 +877,9 @@ class Parser : public ParserBase<Parser> {
   V8_INLINE static ZoneList<Expression*>* NullExpressionList() {
     return nullptr;
   }
+  V8_INLINE static ZoneList<Statement*>* NullStatementList() {
+    return nullptr;
+  }
 
   // Non-NULL empty string.
   V8_INLINE const AstRawString* EmptyIdentifierString() const {