Fix the system property tests to use $ANDROID_DATA.

This lets them work on the host.

Change-Id: I771ccc67652ae37451b45859c7831116cd830086
Fix statvfs tests for the host.

Using /proc seems like a better idea because it's more similar across devices.
I've switched to ensuring we check the initial and final elements in the struct
too, so we have more reason to believe the whole struct is converted correctly.

Change-Id: Ia23403369485747c1452292f6c9df2bb233c04fb
Fix header file dependencies.

MIPS' asm/fcntl.h assumes a bunch of __kernel_* types are already declared.

Change-Id: Iff701bbb5ede9667a78230c2de3a8f4fe41371c5

Conflicts:
	libc/include/sys/epoll.h
	libc/include/sys/inotify.h
MIPS' pipe(2) is weird, but MIPS' pipe2(2) is the same as everyone else's.

arch/mips/kernel/syscall.c has a special sysm_pipe wrapper, but there's
no special treatment of pipe2 because it carries no historical baggage.

Change-Id: I892c0f690b21992c8a48276a9b732126f18fc0ee
Add __EXPORTED_HEADERS__ as predefined macro.

To weed out stuff like this in uapi/linux/types.h

ifndef __EXPORTED_HEADERS__
warning "Attempt to use kernel headers from user space, see
http://kernelnewbies.org/KernelHeaders"
endif /* __EXPORTED_HEADERS__ */

Change-Id: I6506cea6248f7a3b44a839b98e91bdd0d3a6c4cd

Conflicts:
	libc/kernel/tools/defaults.py
Use hidden visibility for generated stubs whose names begin with underscores.

Change-Id: Idb39fd04b7a14114801624e744e76e0e7913d951

Conflicts:
	libc/arch-x86_64/syscalls/__arch_prctl.S
	libc/arch-x86_64/syscalls/__brk.S
	libc/arch-x86_64/syscalls/__clone.S
	libc/arch-x86_64/syscalls/__epoll_pwait.S
	libc/arch-x86_64/syscalls/__getcpu.S
	libc/arch-x86_64/syscalls/__getcwd.S
	libc/arch-x86_64/syscalls/__getpriority.S
	libc/arch-x86_64/syscalls/__ioctl.S
	libc/arch-x86_64/syscalls/__openat.S
	libc/arch-x86_64/syscalls/__ppoll.S
	libc/arch-x86_64/syscalls/__pselect6.S
	libc/arch-x86_64/syscalls/__ptrace.S
	libc/arch-x86_64/syscalls/__reboot.S
	libc/arch-x86_64/syscalls/__rt_sigaction.S
	libc/arch-x86_64/syscalls/__rt_sigpending.S
	libc/arch-x86_64/syscalls/__rt_sigprocmask.S
	libc/arch-x86_64/syscalls/__rt_sigsuspend.S
	libc/arch-x86_64/syscalls/__rt_sigtimedwait.S
	libc/arch-x86_64/syscalls/__sched_getaffinity.S
	libc/arch-x86_64/syscalls/__syslog.S
	libc/arch-x86_64/syscalls/__timer_create.S
	libc/arch-x86_64/syscalls/__timer_delete.S
	libc/arch-x86_64/syscalls/__timer_getoverrun.S
	libc/arch-x86_64/syscalls/__timer_gettime.S
	libc/arch-x86_64/syscalls/__timer_settime.S
	libc/arch-x86_64/syscalls/__waitid.S