stdin/stdout/stderr are special; their mutexes are initialized by
__sinit. There's no unit test for this, because __sinit has already
been called by the time the first unit test runs, but you could
reproduce this failure with a trivial main() that calls flockfile
or ftrylockfile on one of the standard streams before otherwise
using stdio.
Bug: 18208568
Change-Id: I28d232cf05a9f198a2bed61854d8047b23d2091d
This also gets us the C99 wcstoimax and wcstoumax, and a working fgetwc and
ungetwc, all of which are needed in the implementation.
This also brings several other files closer to upstream.
Change-Id: I23b025a8237a6dbb9aa50d2a96765ea729a85579
