Addressed perf regression in Browsermark2.0 array blur test

src/ast.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1586 matching lines @@
   ZoneList<Expression*>* values() const { return values_; }
 
   // Return an AST id for an element that is used in simulate instructions.
   BailoutId GetIdForElement(int i) {
     return BailoutId(first_element_id_.ToInt() + i);
   }
 
   // Populate the constant elements fixed array.
   void BuildConstantElements(Isolate* isolate);
 
+  enum Flags {
+    kNoFlags = 0,
+    kShallowElements = 1,
+    kDisableMementos = 1 << 1
+  };
+
  protected:
   ArrayLiteral(Isolate* isolate,
                ZoneList<Expression*>* values,
                int literal_index,
                int pos)
       : MaterializedLiteral(isolate, literal_index, pos),
         values_(values),
         first_element_id_(ReserveIdRange(isolate, values->length())) {}
 
  private:
@@ skipping 1668 matching lines @@
  private:
   Isolate* isolate_;
   Zone* zone_;
   Visitor visitor_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_AST_H_