ndk: <sys/cdefs.h>: make wchar_t 32-bit for all API levels.

This patch ensures that wchar_t is a 32-bit number when targetting
API level < 9 (i.e. Froyo or older).

You can restore the previous (and broken) behaviour by defining
_WCHAR_IS_8BIT at compile time. See http://b.android.com/57267
for more context.

BUG=57267

Change-Id: Ib334e8fe95a3f592d5d4bb157b0f123984133597
3 files changed