DO NOT MERGE Add DND Settings suggestion

Test: SettingsSuggestionsTest, ZenOnboardingActivityTest
Change-Id: Ie78c9cf8287ee56bc4596efe20d27f8eb432ab6c
Bug: 78445134

src/com/android/settings/notification/ZenModeBackend.java

@@ -135,6 +135,9 @@ public class ZenModeBackend {
     }
 
     protected void saveVisualEffectsPolicy(int category, boolean suppress) {
+        Settings.Global.putInt(mContext.getContentResolver(),
+                Settings.Global.ZEN_SETTINGS_UPDATED, 1);
+
         int suppressedEffects = getNewSuppressedEffects(suppress, category);
         savePolicy(mPolicy.priorityCategories, mPolicy.priorityCallSenders,
                 mPolicy.priorityMessageSenders, suppressedEffects);