Removing NavigationClient dependencies from Tab.

content/public/android/java/src/org/chromium/content/browser/NavigationClient.java

-// Copyright 2013 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.
-
-package org.chromium.content.browser;
-
-import org.chromium.content_public.browser.NavigationHistory;
-
-/**
- * Provides functionality needed to query and page history and the ability to access
- * items in the history.
- */
-public interface NavigationClient {
-
-    /**
-     * Get a directed copy of the navigation history of the view.
-     * @param isForward Whether the returned history should be entries after the current entry.
-     * @param itemLimit The limit on the number of items included in the history.
-     * @return A directed navigation for the page.
-     */
-    public NavigationHistory getDirectedNavigationHistory(boolean isForward, int itemLimit);
-
-    /**
-     * Navigates to the specified index in the navigation entry for this page.
-     * @param index The navigation index to navigate to.
-     */
-    public void goToNavigationIndex(int index);
-}