解决：铃声改变，来短信，短信设置中默认铃声的名称没有同步更新

短信界面没有关闭的情况下，在设置中进行操作，短信设置界面中不会进行刷新。因此在当MessagingPreferenceActivity处于活动（onResume）的时候重新初始化，添加代码如下：

protected void onResume() {

super.onResume();

loadPrefs();

// Since the enabled notifications pref can be changed outside of this activity,

// we have to reload it whenever we resume.

setEnabledNotificationsPref();

// Initialize the sms signature

updateSignatureStatus();

registerListeners();

boolean airplaneModeOn = isAirplaneModeOn();

// Caused by the ICC card state maybe changed outside of this activity,

// we need to update the state of the SMSC preference.

updateSMSCPref(ALL_SUB, airplaneModeOn);

}