Additional fixes for prerender/instant + browsing history.

chrome/test/base/render_view_test.cc

 // Copyright (c) 2011 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 "chrome/test/base/render_view_test.h"
 
 #include "chrome/browser/extensions/extension_function_dispatcher.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/print_messages.h"
 #include "chrome/common/render_messages.h"
@@ skipping 301 matching lines @@
   mouse_event.x = bounds.CenterPoint().x();
   mouse_event.y = bounds.CenterPoint().y();
   mouse_event.clickCount = 1;
   ViewMsg_HandleInputEvent input_event(0);
   scoped_ptr<IPC::Message> input_message(new ViewMsg_HandleInputEvent(0));
   input_message->WriteData(reinterpret_cast<const char*>(&mouse_event),
                            sizeof(WebMouseEvent));
   view_->OnMessageReceived(*input_message);
   return true;
 }
+
+void RenderViewTest::ClearHistory() {
+  view_->page_id_ = -1;
+  view_->history_list_offset_ = -1;
+  view_->history_list_length_ = 0;
+  view_->history_page_ids_.clear();
+}