Clean up TrackingVolume un-needlessy declared as const
In various places we were declaring TrackingVolumes as const, and then we were manipulating them later on in the call chain.
We do no need to create new Tracking Volumes as const as a starting point. Especially if the next step is manipulate/fill them by passing them to relevant tools ....
So the proper idea seems to be (done in other MT related migrations) :
- Let's create them as non-const
- manipulate/ add to them/ glue them together,
- when we are done access them later on
as constvia proper
This MR is step 0, the basic prequisite for cleaning up of all the helpers/processors etc etc.
It avoids a few
const_cast and marks back some methods as