Undo the changes introduced in #5377. This is a trade-off where it
is considerd better to have as much memory as possible allocated
by the allocator, with the risk that it will be freed when still
in use. Than to have significant amounts of memory allocated outside
of the allocator.

It should be noted that because of Go's garbage collector it is
perfectly safe for memory to be "freed" when still in use. It just
mean that any accounting done by the allocator will be inaccurate.

Remove the recently added StringRef type as it is now unnecessary.