EditViewdefs file missing after upgrading to new version of SugarCRM

We were on version 7.x, we upgraded to version 8.x. If I go to the path 

custom/modules/<modulename >/metadata. I find that the file editviewdefs.php is missing.

I tried to go to the studio> ModuleName>layouts>save and deploy, it does not generate the editviewdefs.php file.

I also tried to copy the file from the directory

modules/<moduleName>/metadata , The custom javascript added does not work.

There is a backup file with extension suback.php.

Any thoughts over here. What is want to do is to write a custom javascript file for the module.