An android application have two modules and one depend on the other, and the common used jars and native libraries are defined in parent-project, while the child-project add it as a dependency in the build.gradle:

However after I build the child-project I found that the jars put insiede the parent-project are copied to the apk, while the native libraries are not. Only the native libraries inside the child-project are packaged to the apk.
What's going on?
With Android studio 1.0.2.