OTA升级后概率性出现卡在开机动画界面无法退出
OTA升级之后，手机会概率性卡在开机动画界面，log 显示 media.player died:
01-01 20:06:46.273062 288 288 E art : Cannot patch secondary image '/system/framework/boot-framework.art', clearing dalvik_cache and restarting zygote. //<==zygote重启
01-01 20:06:46.298441 247 247 I ServiceManager: service 'media.player' died
01-01 20:06:46.306115 513 574 D BootAnimation: threadLoop() movie() //<==开始播放开机动画
导致开机动画退出不了，也没有开机铃声播放。
原因：
OTA之后第一次开机，由于zygote检测到boot-framework.art这支文件的校验和不对（system分区在OTA升级后会更新，但是data分区下的文件在OTA升级中不更新仍旧是旧版本的，造成data和system目录下的.art、.oat文件不匹配），于是clearing了dalvik-cache里面的内容。zygote重启，zygote挂掉之后，引起media server挂掉，进而导致没有声音。也无法满足开机动画退出条件checkExit();。
解决方法：
修改BootAnimation.cpp：
491bool BootAnimation::threadLoop()
492{
……
498 status_tmediastatus = NO_ERROR;
……
508 if (mediastatus == NO_ERROR) {
509 ALOGD("mediaplayer is initialized");
510 Parcel* attributes = new Parcel();
511 attributes->writeInt32(AUDIO_USAGE_MEDIA); //usage
512 attributes->writeInt32(AUDIO_CONTENT_TYPE_MUSIC); //audio_content_type_t
513 attributes->writeInt32(AUDIO_SOURCE_DEFAULT); //audio_source_t
514 attributes->writeInt32(0); //audio_flags_mask_t
515 attributes->writeInt32(1); //kAudioAttributesMarshallTagFlattenTags of mediaplayerservice.cpp
516 attributes->writeString16(String16("BootAnimationAudioTrack")); // tags
517 mediaplayer->setParameter(KEY_PARAMETER_AUDIO_ATTRIBUTES, *attributes);
518 mediaplayer->setAudioStreamType(AUDIO_STREAM_MUSIC);
519 mediastatus = mediaplayer->prepare();
520 }
521 if (mediastatus == NO_ERROR) {
522 ALOGD("media player is prepared");
523 mediastatus = mediaplayer->start();
524 }
//If the mediastatus is not NO_ERROR, mBootVideoPlayState = MEDIA_ERROR.
if(mediastatus != NO_ERROR){ //add code
mBootVideoPlayState = MEDIA_ERROR; //add code
} //add code