Revert "Frameworks/base: Refactor UserHandle and Environment a bit"

Breaks monkey in root mode.

This reverts commit 6e16714c68.

Bug: 29338430
Change-Id: I238f89dad77d7dcae6d02eccbda52eb9c6c6466c

services/java/com/android/server/SystemServer.java

@@ -284,9 +284,6 @@ public final class SystemServer {
             // we've defined it before booting further.
             Build.ensureFingerprintProperty();
 
-            // Initialize Environment for the system user.
-            Environment.init();
-
             // Within the system server, it is an error to access Environment paths without
             // explicitly specifying a user.
             Environment.setUserRequired(true);