The Android™ SELinux code and policy developed by the SE for Android project has been merged to mainline Android as of the Android 5.0 (Lollipop) release, although further work continues in the Android Open Source Project (AOSP) master branch. Android 4.3 was the first Android release version to enable the original SELinux support contributed by the SE for Android project. Android 4.4 put SELinux into enforcing mode for the first time, beginning by confining a specific set of root daemons. Android 5.0 (and later) extends SELinux protection to all services and apps on Android. Android 6.0 further applies SELinux to enforcing specific security goals.
The Android SELinux support is discussed in https://source.android.com/devices/tech/security/selinux/index.html.
As a result of the merging of these security enhancements into mainline Android, the SE for Android project is no longer maintaining its own separate repositories and branches. If you wish to leverage or further build upon these security enhancements, you should directly work from the appropriate AOSP branches.Android™ is a trademark of Google, Inc.