Mark two MediaNotification tests as flaky

chrome/android/javatests/src/org/chromium/chrome/browser/media/ui/NotificationTitleUpdatedTest.java

Index: chrome/android/javatests/src/org/chromium/chrome/browser/media/ui/NotificationTitleUpdatedTest.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/media/ui/NotificationTitleUpdatedTest.java b/chrome/android/javatests/src/org/chromium/chrome/browser/media/ui/NotificationTitleUpdatedTest.java
index 263c13dd9f3b369de308595d21cbdda9509ae860..f8101c5dbe5d3432116cc658bf8ab2a85c36ae72 100644
--- a/chrome/android/javatests/src/org/chromium/chrome/browser/media/ui/NotificationTitleUpdatedTest.java
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/media/ui/NotificationTitleUpdatedTest.java
@@ -13,6 +13,7 @@ import android.widget.TextView;
 
 import org.chromium.base.ObserverList;
 import org.chromium.base.ThreadUtils;
+import org.chromium.base.test.util.FlakyTest;
 import org.chromium.base.test.util.Restriction;
 import org.chromium.base.test.util.RetryOnFailure;
 import org.chromium.chrome.R;
@@ -176,6 +177,7 @@ public class NotificationTitleUpdatedTest extends ChromeActivityTestCaseBase<Chr
         assertTitleMatches("title3");
     }
 
+    @FlakyTest(message = "crbug.com/697453")
     @SmallTest
     public void testMediaMetadataPersistsAfterSamePageNavigation() throws Throwable {
         ensureTestServer();