Add offset for native stack dump.

When dumping the stack from a shared library loaded out of an apk,
the art stack dumper didn't match the backtrace unwinding code and
include an offset. Add that back in so that this backtrace can be
passed to go/as.

Test: Loaded an app with a shared library from an apk and did a kill -3.
Test: Observed that the offset value is set properly.
Change-Id: I881946330e76b9aab28cf7dbd94fe406bac7895a
1 file changed