For android, gc builds with buildmode=pie by default, and
as a result, the compiled packages are not installed in
the usual pkg/$GOOS_$GOARCH pack. Copy the compiled packages
in pkg/android_$GOARCH_shared into the pkg/android_$GOARCH
in the test device.

Change-Id: I909e4cc7095ac95ef63bdf6ddc4cb2c698f3459e
Reviewed-on: https://go-review.googlesource.com/16151Reviewed-by: David Crawshaw <crawshaw@golang.org>