Respect extractNativeLibs in natively bridged environments

The extractNativeLibs property was ignored by the package installer
for environments with native bridge. This is not neccessary since
native bridge implementations are required to support
open-directly-from-apk feature and in this respect are not different
from environments without native bridge.

Bug: http://b/116854266
Test: cts-tradefed run singleCommand cts --skip-preconditions -m CtsJniTestCases
Change-Id: I9ea7397183d7ebe2c00e461b95d188b15b51eca2