Add RecentTabsPageTest

chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentlyClosedTabManager.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentlyClosedTabManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentlyClosedTabManager.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentlyClosedTabManager.java
new file mode 100644
index 0000000000000000000000000000000000000000..3ea0113e97c7cffbd64cbe25e470ed3c282682de
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentlyClosedTabManager.java
@@ -0,0 +1,56 @@
+// Copyright 2017 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.chrome.browser.ntp;
+
+import android.support.annotation.Nullable;
+
+import org.chromium.chrome.browser.tab.Tab;
+
+import java.util.List;
+
+/**
+ * Manages a list of recently closed tabs.
+ */
+public interface RecentlyClosedTabManager {
+    /**
+     * Sets the {@link Runnable} to be called whenever the list of recently closed tabs changes.
+     * @param runnable The {@link Runnable} to be called, or null.
+     */
+    void setTabsUpdatedRunnable(@Nullable Runnable runnable);
+
+    /**
+     * @param maxTabCount The maximum number of recently closed tabs to return.
+     * @return A snapshot of the list of recently closed tabs, with up to maxTabCount elements.
+     */
+    List<RecentlyClosedTab> getRecentlyClosedTabs(int maxTabCount);
+
+    /**
+     * Opens a recently closed tab in the current tab or a new tab. If opened in the current tab,
+     * the current tab's entire history is replaced.
+     *
+     * @param tab The current Tab.
+     * @param recentTab The RecentlyClosedTab to open.
+     * @param windowOpenDisposition The WindowOpenDisposition value specifying whether to open in
+     *         the current tab or a new tab.
+     * @return Whether the tab was successfully opened.
+     */
+    boolean openRecentlyClosedTab(Tab tab, RecentlyClosedTab recentTab, int windowOpenDisposition);
+
+    /**
+     * Opens the most recently closed tab in a new tab.
+     */
+    void openRecentlyClosedTab();
+
+    /**
+     * Clears all recently closed tabs.
+     */
+    void clearRecentlyClosedTabs();
+
+    /**
+     * To be called before this instance is abandoned to the garbage collector so it can do any
+     * necessary cleanups. This instance must not be used after this method is called.
+     */
+    void destroy();
+}