Re-enable BrowserTest.WindowOpenClose2

This test doesn't seem to flake locally anymore.

Bug: 867163
Change-Id: I7d73e63237739b7d173023011af64af3917e2969
Reviewed-on: https://chromium-review.googlesource.com/1217283Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Fady Samuel <fsamuel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590310}

chrome/browser/ui/browser_browsertest.cc

@@ -1891,13 +1891,7 @@ IN_PROC_BROWSER_TEST_F(BrowserTest, MAYBE_WindowOpenClose1) {
   EXPECT_EQ(title, title_watcher.WaitAndGetTitle());
 }
 
-// Flaky on Chrome OS, Linux and Windows. TODO(https://crbug.com/823043) fix it.
-#if defined(OS_CHROMEOS) || defined(OS_LINUX) || defined(OS_WIN)
-#define MAYBE_WindowOpenClose2 DISABLED_WindowOpenClose2
-#else
-#define MAYBE_WindowOpenClose2 WindowOpenClose2
-#endif
-IN_PROC_BROWSER_TEST_F(BrowserTest, MAYBE_WindowOpenClose2) {
+IN_PROC_BROWSER_TEST_F(BrowserTest, WindowOpenClose2) {
   base::CommandLine::ForCurrentProcess()->AppendSwitch(
       switches::kDisablePopupBlocking);
   ASSERT_TRUE(embedded_test_server()->Start());