Given it's intended to be an internal implementation class, we can move
it into the cpp file to ensure that.
This also lets us move some header dependencies into the cpp file as
well.
Given the expression involves a 32-bit value, this simplifies down to
just: 0x3ffffff. This is likely a remnant from testing that was never
cleaned up.
Resolves a -Wshift-overflow warning.
The purpose of make_pair is generally to deduce the types within the
pair without explicitly specifying the types, so these usages were
generally unnecessary, particularly when the type is enforced by the
array declaration.