Add libprofile-extras to all link steps when NATIVE_COVERAGE is enabled.

libprofile-extras has a wrapper to getenv() that appends the effective
userid (euid) of the current process to GCOV_PREFIX.  This avoids
conflicts and permissions issues when multiple processes try to
create/access the same directories and files under /data/misc/trace.

This library needs to be added and the -Wl,--wrap,getenv flag needs to
be passed to all link steps.  Since Android.mk does not propagate flags
and libraries across dependencies, this change just adds the library and
flag to all non-static-library Android.mk modules.  As a consequence,
*ALL* binaries created via Android.mk will have the signal handler and
property watcher thread in libprofile-extras but they are no-ops in
non-coverage-enabled binaries.

The dependency is added early enough in core/binary.mk so that the
LOCAL_SOONG_LINK_TYPE resolutions occur correctly.

Test: Verify that coverage files are written to
/data/misc/trace/<euid>/proc/... instead of /data/misc/trace/proc/...

Change-Id: I4d5f849c15e9a278253f2148185ddf3ab2878e2f