Unify and fix checkers for duplicate object literal properties.

src/parser.h

Index: src/parser.h
diff --git a/src/parser.h b/src/parser.h
index efb7706086d20d3c59ecd8ac6303ea6dc70b0a37..e5853bd582488cae0bbfba41bbdb901ab5813db2 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -463,7 +463,7 @@ class Parser BASE_EMBEDDED {
 
   void ReportMessageAt(Scanner::Location loc,
                        const char* message,
-                       Vector<const char*> args);
+                       Vector<const char*> args = Vector<const char*>::empty());
   void ReportMessageAt(Scanner::Location loc,
                        const char* message,
                        Vector<Handle<String> > args);
@@ -671,7 +671,6 @@ class Parser BASE_EMBEDDED {
   Expression* ParsePrimaryExpression(bool* ok);
   Expression* ParseArrayLiteral(bool* ok);
   Expression* ParseObjectLiteral(bool* ok);
-  ObjectLiteral::Property* ParseObjectLiteralGetSet(bool is_getter, bool* ok);
   Expression* ParseRegExpLiteral(bool seen_equal, bool* ok);
 
   // Populate the constant properties fixed array for a materialized object
@@ -879,6 +878,7 @@ class Parser BASE_EMBEDDED {
   CompilationInfo* info_;
   friend class BlockState;
   friend class FunctionState;
+  friend class ObjectLiteralChecker<Parser>;
 };