Class fields, part 1 (parsing and infrastructure)

src/ast/scopes.h

Index: src/ast/scopes.h
diff --git a/src/ast/scopes.h b/src/ast/scopes.h
index 96fcc5141be46124a8478b2e56723f516e9fd1ca..61228a2ec41bad28e166ffcb3941d5f91560396e 100644
--- a/src/ast/scopes.h
+++ b/src/ast/scopes.h
@@ -678,6 +678,10 @@ class DeclarationScope : public Scope {
   // Returns the default function arity excluding default or rest parameters.
   int default_function_length() const { return arity_; }
 
+  // Normal code should not need to call this. Class field initializers use this
+  // property to store information about the number of fields.
+  void set_default_function_length(int arity) { arity_ = arity; }
+
   // Returns the number of formal parameters, excluding a possible rest
   // parameter.  Examples:
   //   function foo(a, b) {}         ==> 2