source of the aforementioned build breakage was then errant include of
this header when stddef.h was intended. Nothing in this file uses any
of the symbols exported from stdint.h, only symbols from stddef.h.
This is needed by the MemoryFile changes in
https://android-git.corp.google.com/g/2714
where it is used to find out whether a file descriptor
refers to an ashmem region.