[DevTools] Enable DevToolsBeforeUnloadTest.TestDevToolsOnDevTools

chrome/browser/devtools/devtools_sanity_browsertest.cc

 // Copyright (c) 2012 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 <stddef.h>
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/cancelable_callback.h"
@@ skipping 792 matching lines @@
       GetInspectedTab(), false);
 
   OpenDevToolsPopupWindow(devtools_window);
   CloseDevToolsPopupWindow(devtools_window);
 }
 
 // Tests that BeforeUnload event gets called on devtools that are opened
 // on another devtools.
 // Disabled because of http://crbug.com/497857
 IN_PROC_BROWSER_TEST_F(DevToolsBeforeUnloadTest,
-                       DISABLED_TestDevToolsOnDevTools) {
+                       TestDevToolsOnDevTools) {
   ASSERT_TRUE(spawned_test_server()->Start());
   LoadTestPage(kDebuggerTestPage);
 
   std::vector<DevToolsWindow*> windows;
   std::vector<content::WindowedNotificationObserver*> close_observers;
   content::WebContents* inspected_web_contents = GetInspectedTab();
   for (int i = 0; i < 3; ++i) {
     DevToolsWindow* devtools_window = OpenDevToolWindowOnWebContents(
       inspected_web_contents, i == 0);
     windows.push_back(devtools_window);
@@ skipping 509 matching lines @@
 
   SimulateTapAt(web_contents, gfx::Point(30, 60));
   DispatchInPageAndWait("waitForEvent", "gesturetap");
 
   DispatchAndWait("stopTimeline");
   RunTestMethod("checkInputEventsPresent", "MouseMove", "MouseDown",
                 "MouseWheel", "GestureTap");
 
   CloseDevToolsWindow();
 }