This is an efficient string storage for short strings without heap allocations,
and falling back to the heap for bigger allocations. Almost all structure fields
and structure names in use nowadays are short enough to not require a heap
allocation.
As structure names and fields are sometimes dynamically created, storing them in
a GQuark can create a memory leak and potentially a DoS attack by continously
triggering creating of new quarks.
Thanks to Tim for coming up with the name!
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/7432>
