Revert of Disable UndoTabModelTest#testUndoNotSupported

chrome/android/javatests/src/org/chromium/chrome/browser/tabmodel/UndoTabModelTest.java

 // Copyright 2015 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.tabmodel;
 
 import android.annotation.TargetApi;
 import android.os.Build;
 import android.test.suitebuilder.annotation.MediumTest;
 
@@ skipping 1372 matching lines @@
      * Test a {@link TabModel} where undo is not supported:
      *     Action                     Model List         Close List        Comprehensive List
      * 1.  Initial State              [ 0 1 2 3s ]       -                 [ 0 1 2 3s ]
      * 2.  CloseTab(1, allow undo)    [ 0 2 3s ]         -                 [ 0 2 3s ]
      * 3.  CloseAll                   -                  -                 -
      *
      * @throws InterruptedException
      */
     @MediumTest
     @RetryOnFailure
-    @DisabledTest(message = "crbug.com/674654")
     public void testUndoNotSupported() throws InterruptedException {
         TabModel model = getActivity().getTabModelSelector().getModel(true);
         ChromeTabCreator tabCreator = getActivity().getTabCreator(true);
         createTabOnUiThread(tabCreator);
         createTabOnUiThread(tabCreator);
         createTabOnUiThread(tabCreator);
         createTabOnUiThread(tabCreator);
 
         Tab tab0 = model.getTabAt(0);
         Tab tab1 = model.getTabAt(1);
@@ skipping 255 matching lines @@
         openMostRecentlyClosedTabOnUiThread(firstSelector);
         assertEquals("Closed tab in second window should be restored in the first window.", 2,
                 firstModel.getCount());
         Tab tab0 = firstModel.getTabAt(0);
         Tab tab1 = firstModel.getTabAt(1);
         Tab[] firstWindowTabs = new Tab[]{tab0, tab1};
         checkState(firstModel, firstWindowTabs, tab0, EMPTY, firstWindowTabs, tab0);
         assertEquals(TEST_URL_1, tab1.getUrl());
     }
 }