Fixed policy monitoring empty device list issue

components/device-mgt/org.wso2.carbon.device.mgt.mobile.impl/src/main/java/org/wso2/carbon/device/mgt/mobile/impl/android/AndroidPolicyMonitoringService.java

@@ -46,7 +46,7 @@ public class AndroidPolicyMonitoringService implements PolicyMonitoringService {
     @Override
     public void notifyDevices(List<Device> list) throws PolicyComplianceException {
         GCMService gcmService = MobileDeviceManagementDataHolder.getInstance().getGCMService();
-        if (gcmService.isGCMEnabled()) {
+        if (gcmService.isGCMEnabled() && !list.isEmpty()) {
             gcmService.sendNotification("POLICY_BUNDLE", list);
         }
     }