Set LOCAL_EXPORT_C_INCLUDE_DIRS in Android.mk.

Export the lib/ directory to increase compatibility with
third-party code that includes <expat.h>.

(Android.mk currently copies expat.h and expat_external.h to
/usr/include/libexpat, but this location is non-standard.)

Bug: 22328216
Change-Id: I49bbf60be9e7cf6f859bcb993019ff3807cf6fd1
1 file changed