Is your feature request related to a problem? Please describe.
Raised by #9859. Currently, we can use either parking_lot synchronization, std, or refcell (in no_std contexts). This is influenced by the parking_lot and std features. I don't see why we would need std synchronization over parking lot. This might be an unexpected performance factor when people decide to only use the features they need.
Describe the solution you'd like
Remove the feature flag and always use refcell or parking_lot.
Describe alternatives you've considered
Not changing this if there's a reason for it
Additional context
Add any other context or screenshots about the feature request here.
Is your feature request related to a problem? Please describe.
Raised by #9859. Currently, we can use either parking_lot synchronization, std, or refcell (in no_std contexts). This is influenced by the parking_lot and std features. I don't see why we would need std synchronization over parking lot. This might be an unexpected performance factor when people decide to only use the features they need.
Describe the solution you'd like
Remove the feature flag and always use refcell or parking_lot.
Describe alternatives you've considered
Not changing this if there's a reason for it
Additional context
Add any other context or screenshots about the feature request here.