Not that I thought about this change too deeply, but in the original implementation I preferred the clarity
of using the helper functions from android headers over more obscure foo->bar.close(&stuff). The only
problem was that the helpers are not always available, which was fixed by having similar functions - with
mce_ prefix for obvious reasons. So IMO
- the xxx_open() functions hide ugliness
- once you have xxx_open(), having xxx_close() provides symmetry
- the helper names are self documenting
- clarity of intent wins over minor optimizations