Properly handle non split system user when showing bouncer

For system user, there should be no atempt to dismiss keyguard,
but only if system user is split (i.e. not a meat user).

Change-Id: Ia2c1e7a3e197c5be72446f21b3883e853485ff26
(cherry picked from commit aa401afb4cdfd5bab441e633aee801c2a127aec2)
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardBouncer.java b/packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardBouncer.java
index aecef14..190e37f 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardBouncer.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardBouncer.java
@@ -19,6 +19,7 @@
 import android.app.ActivityManager;
 import android.content.Context;
 import android.os.UserHandle;
+import android.os.UserManager;
 import android.util.Slog;
 import android.view.KeyEvent;
 import android.view.LayoutInflater;
@@ -91,7 +92,8 @@
 
         final int activeUserId = ActivityManager.getCurrentUser();
         final int keyguardUserId = KeyguardUpdateMonitor.getCurrentUser();
-        final boolean allowDismissKeyguard = activeUserId != UserHandle.USER_SYSTEM
+        final boolean allowDismissKeyguard =
+                !(UserManager.isSplitSystemUser() && activeUserId == UserHandle.USER_SYSTEM)
                 && activeUserId == keyguardUserId;
         // If allowed, try to dismiss the Keyguard. If no security auth (password/pin/pattern) is
         // set, this will dismiss the whole Keyguard. Otherwise, show the bouncer.