Move AcceptWithResponder() out of the MessageReceiver interface.

mojo/public/cpp/bindings/tests/validation_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stdio.h>
 
 #include <algorithm>
 #include <sstream>
 #include <string>
 #include <vector>
@@ skipping 78 matching lines @@
 
   std::string result = func(&message);
   EXPECT_EQ(expected, result) << "failed test: " << root;
 }
 
 class DummyMessageReceiver : public MessageReceiver {
  public:
   virtual bool Accept(Message* message) MOJO_OVERRIDE {
     return true;  // Any message is OK.
   }
-  virtual bool AcceptWithResponder(Message* message,
-                                   MessageReceiver* responder) MOJO_OVERRIDE {
-    assert(false);
-    return false;
-  }
 };
 
 std::string DumpMessageHeader(Message* message) {
   DummyMessageReceiver not_reached_receiver;
   internal::MessageHeaderValidator validator(&not_reached_receiver);
   bool rv = validator.Accept(message);
   if (!rv)
     return "ERROR\n";
 
   std::ostringstream os;
@@ skipping 11 matching lines @@
   std::vector<std::string> header_tests =
       GetMatchingTests(names, "validate_header_");
 
   for (size_t i = 0; i < header_tests.size(); ++i)
     RunValidationTest(header_tests[i], &DumpMessageHeader);
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace mojo