Move away from custom conditions on controllers

After #2871910: Standardize on DrupalDefaultEntityController, following guidelines in the base class is the next step.
In special it is recommended to move away from conditions parameter on load(), so #2897078: Operation controller does not cache when custom conditions are used was in a way a step back.
Let's get rid of custom conditions in favour if using EntityFieldQuery class.

This may involve at least changing operation controller to remove the 3 custom conditions.