Disable BrowserTest.InterstitialCloseTab which is flaky.

chrome/browser/ui/browser_browsertest.cc

Index: chrome/browser/ui/browser_browsertest.cc
diff --git a/chrome/browser/ui/browser_browsertest.cc b/chrome/browser/ui/browser_browsertest.cc
index d9a1b24c0f7070b178f11543119b916aa977c6be..4e85b9d6d89b494d896120b6f40a226b399c04d4 100644
--- a/chrome/browser/ui/browser_browsertest.cc
+++ b/chrome/browser/ui/browser_browsertest.cc
@@ -1979,8 +1979,13 @@ IN_PROC_BROWSER_TEST_F(BrowserTest, InterstitialClosesDialogs) {
   EXPECT_FALSE(contents->GetRenderProcessHost()->IgnoreInputEvents());
 }
 
-
-IN_PROC_BROWSER_TEST_F(BrowserTest, InterstitialCloseTab) {
+#if defined(OS_MACOSX)
+// http://crbug.com/393218
+#define MAYBE_InterstitialCloseTab DISABLED_InterstitialCloseTab
+#else
+#define MAYBE_InterstitialCloseTab InterstitialCloseTab
+#endif
+IN_PROC_BROWSER_TEST_F(BrowserTest, MAYBE_InterstitialCloseTab) {
   WebContents* contents = browser()->tab_strip_model()->GetActiveWebContents();
 
   {