Recovering Information(Contacts,Messages) from the Android Backup file
there are some ideas to restore backup and reset screenlock without flashing anything.

if still interested please come back to forum.xda-developers.com and answer my question regarding solution C.

solution A is easiest way, but i have not tested
1. create userdata_20160208_095026.backup
2. root the phone. don't flash custom recovery
3. factory reset
4. copy /data/data/com.android.providers.settings/databases/settings.db to /cache
5. install some shell script to copy back settings.db on every boot
6. restore userdata_20160208_095026.backup with stock recovery

solution B, tested on MT6582 Jelly Bean, works!
(because some phones dont have fastboot and its difficult to flash)
1. use my script to convert stock backup to cwm backup
2. root the phone. don't flash custom recovery
3. install stericson.busybox and jackpal.androidterm
4. insert sdcard with ext2 partition
5. mount ext2 partition
6. copy /data to sdcard
7. unmount /data partition and symlink sdcard to /data
8. mount /data partition to /cache/data
9. unpack cwm backup
10. replace settings.db

solution C (with flashing) tested on MT6582 works!
1. use my script to convert stock backup to cwm backup
2. replace settings.db in cwm backup
3. root the phone
4. flash custom recovery
5. restore cwm backup

currently i am writing a shell script for solution B. it works at moment for cwm backup only, try to fix up some errors regarding stock backup...