Add metrics for settings conditionals

Bug: 27851236
Change-Id: I400716457d3f628419410a02c2a457d41d19a067

src/com/android/settings/dashboard/conditional/DndCondition.java

@@ -24,6 +24,7 @@ import android.content.Intent;
 import android.graphics.drawable.Icon;
 import android.provider.Settings;
 import android.service.notification.ZenModeConfig;
+import com.android.internal.logging.MetricsProto.MetricsEvent;
 import com.android.settings.R;
 
 public class DndCondition extends Condition {
@@ -112,6 +113,11 @@ public class DndCondition extends Condition {
         }
     }
 
+    @Override
+    public int getMetricsConstant() {
+        return MetricsEvent.SETTINGS_CONDITION_DND;
+    }
+
     public static class Receiver extends BroadcastReceiver {
         @Override
         public void onReceive(Context context, Intent intent) {