Revert "Added a 4th param to data label format callback"

This reverts commit 8719b3853743a5b53c80d0c9b125f60590c2c866.
Revert "Revert "Added a 4th param to data label format callback""

This reverts commit 1852f80ee99c2595882522c8fb5acfb7807bbec3.