Implement handling of arrow functions in the parser

src/ast.h

Index: src/ast.h
diff --git a/src/ast.h b/src/ast.h
index c6ee71ed83ed613ab121f2f9b80fdc9712f619b7..cdc8e70e5ad9f9d88e1006cb4c201013b0cfcf1f 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -2309,6 +2309,11 @@ class FunctionLiteral V8_FINAL : public Expression {
     kNotGenerator
   };
 
+  enum IsArrowFlag {
+    kIsArrow,
+    kNotArrow
+  };
+
   DECLARE_NODE_TYPE(FunctionLiteral)
 
   Handle<String> name() const { return name_; }
@@ -2371,6 +2376,10 @@ class FunctionLiteral V8_FINAL : public Expression {
     return IsGenerator::decode(bitfield_) == kIsGenerator;
   }
 
+  bool is_arrow() {
+    return IsArrow::decode(bitfield_) == kIsArrow;
+  }
+
   int ast_node_count() { return ast_properties_.node_count(); }
   AstProperties::Flags* flags() { return ast_properties_.flags(); }
   void set_ast_properties(AstProperties* ast_properties) {
@@ -2405,6 +2414,7 @@ class FunctionLiteral V8_FINAL : public Expression {
                   IsFunctionFlag is_function,
                   IsParenthesizedFlag is_parenthesized,
                   IsGeneratorFlag is_generator,
+                  IsArrowFlag is_arrow,
                   int position)
       : Expression(zone, position),
         name_(name),
@@ -2424,7 +2434,8 @@ class FunctionLiteral V8_FINAL : public Expression {
         HasDuplicateParameters::encode(has_duplicate_parameters) |
         IsFunction::encode(is_function) |
         IsParenthesized::encode(is_parenthesized) |
-        IsGenerator::encode(is_generator);
+        IsGenerator::encode(is_generator) |
+        IsArrow::encode(is_arrow);
   }
 
  private:
@@ -2451,6 +2462,7 @@ class FunctionLiteral V8_FINAL : public Expression {
   class IsFunction: public BitField<IsFunctionFlag, 4, 1> {};
   class IsParenthesized: public BitField<IsParenthesizedFlag, 5, 1> {};
   class IsGenerator: public BitField<IsGeneratorFlag, 6, 1> {};
+  class IsArrow: public BitField<IsArrowFlag, 7, 1> {};
 };
 
 
@@ -3333,12 +3345,13 @@ class AstNodeFactory V8_FINAL BASE_EMBEDDED {
       FunctionLiteral::IsFunctionFlag is_function,
       FunctionLiteral::IsParenthesizedFlag is_parenthesized,
       FunctionLiteral::IsGeneratorFlag is_generator,
+      FunctionLiteral::IsArrowFlag is_arrow,
       int position) {
     FunctionLiteral* lit = new(zone_) FunctionLiteral(
         zone_, name, scope, body,
         materialized_literal_count, expected_property_count, handler_count,
         parameter_count, function_type, has_duplicate_parameters, is_function,
-        is_parenthesized, is_generator, position);
+        is_parenthesized, is_generator, is_arrow, position);
     // Top-level literal doesn't count for the AST's properties.
     if (is_function == FunctionLiteral::kIsFunction) {
       visitor_.VisitFunctionLiteral(lit);