Allow below divider for all EntityHeader

- Create an method in LayoutPreference let other class can
  set divider status.
- EntityHeaderController will allow to have a below divider
  by default.

Test: visual, robotest
Bug: 116346008
Change-Id: Ic041b8fef8d22ce1b7ea48eedfbe97c708c41ce7

src/com/android/settings/applications/LayoutPreference.java

@@ -24,7 +24,6 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.widget.FrameLayout;
 
-import androidx.annotation.VisibleForTesting;
 import androidx.core.content.res.TypedArrayUtils;
 import androidx.preference.Preference;
 import androidx.preference.PreferenceViewHolder;
@@ -37,9 +36,7 @@ public class LayoutPreference extends Preference {
     private final View.OnClickListener mClickListener = v -> performClick(v);
     private boolean mAllowDividerAbove;
     private boolean mAllowDividerBelow;
-
-    @VisibleForTesting
-    View mRootView;
+    private View mRootView;
 
     public LayoutPreference(Context context, AttributeSet attrs) {
         super(context, attrs);
@@ -116,4 +113,11 @@ public class LayoutPreference extends Preference {
         return mRootView.findViewById(id);
     }
 
+    public void setAllowDividerBelow(boolean allowed) {
+        mAllowDividerBelow = allowed;
+    }
+
+    public boolean isAllowDividerBelow() {
+        return mAllowDividerBelow;
+    }
 }

src/com/android/settings/widget/EntityHeaderController.java

@@ -238,6 +238,7 @@ public class EntityHeaderController {
         pref.setOrder(-1000);
         pref.setSelectable(false);
         pref.setKey(PREF_KEY_APP_HEADER);
+        pref.setAllowDividerBelow(true);
         return pref;
     }