Force keyguard if there are multiple users

Otherwise there would be no way to switch users if a user chooses None as lock screen.

Also adjust some layout params for Preference items to align the icons and text.

Change-Id: Ib11bb961edaef90de280bc7137d10b68765aea98

Author: Amith Yamasani

core/res/res/layout/preference_holo.xml

@@ -33,11 +33,12 @@
         android:orientation="horizontal">
         <ImageView
             android:id="@+android:id/icon"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
+            android:layout_width="48dp"
+            android:layout_height="48dp"
             android:layout_gravity="center"
             android:minWidth="48dp"
-            android:paddingRight="@dimen/preference_item_padding_inner"
+            android:scaleType="centerInside"
+            android:layout_marginEnd="@dimen/preference_item_padding_inner"
              />
     </LinearLayout>
 
@@ -56,7 +57,7 @@
             android:textAppearance="?android:attr/textAppearanceMedium"
             android:ellipsize="marquee"
             android:fadingEdge="horizontal" />
-            
+
         <TextView android:id="@+android:id/summary"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"

policy/src/com/android/internal/policy/impl/keyguard/KeyguardViewMediator.java

@@ -41,6 +41,7 @@
 import android.os.SystemClock;
 import android.os.SystemProperties;
 import android.os.UserHandle;
+import android.os.UserManager;
 import android.provider.Settings;
 import android.telephony.TelephonyManager;
 import android.util.EventLog;
@@ -161,6 +162,9 @@ public class KeyguardViewMediator {
     /** High level access to the power manager for WakeLocks */
     private PowerManager mPM;
 
+    /** UserManager for querying number of users */
+    private UserManager mUserManager;
+
     /**
      * Used to keep the device awake while the keyguard is showing, i.e for
      * calls to {@link #pokeWakelock()}
@@ -436,6 +440,7 @@ public void pokeWakelock(long holdMs) {
     public KeyguardViewMediator(Context context, LockPatternUtils lockPatternUtils) {
         mContext = context;
         mPM = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
+        mUserManager = (UserManager) mContext.getSystemService(Context.USER_SERVICE);
         mWakeLock = mPM.newWakeLock(
                 PowerManager.FULL_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP, "keyguard");
         mWakeLock.setReferenceCounted(false);
@@ -779,7 +784,8 @@ private void doKeyguardLocked() {
             return;
         }
 
-        if (mLockPatternUtils.isLockScreenDisabled() && !lockedOrMissing) {
+        if (mUserManager.getUsers().size() < 2
+                && mLockPatternUtils.isLockScreenDisabled() && !lockedOrMissing) {
             if (DEBUG) Log.d(TAG, "doKeyguard: not showing because lockscreen is off");
             return;
         }