Use framework support to customize dividers between prefs.

Bug: 33579296
Test: make RunSettingsRoboTests
Change-Id: I1bb3b82b88dc727cda05b00058e6f40564f0e5db
diff --git a/src/com/android/settings/notification/VolumeSeekBarPreference.java b/src/com/android/settings/notification/VolumeSeekBarPreference.java
index 5ab1d29..8a51961 100644
--- a/src/com/android/settings/notification/VolumeSeekBarPreference.java
+++ b/src/com/android/settings/notification/VolumeSeekBarPreference.java
@@ -59,15 +59,18 @@
     }
 
     public VolumeSeekBarPreference(Context context, AttributeSet attrs, int defStyleAttr) {
-        this(context, attrs, defStyleAttr, 0);
+        super(context, attrs, defStyleAttr);
+        setLayoutResource(R.layout.preference_volume_slider);
     }
 
     public VolumeSeekBarPreference(Context context, AttributeSet attrs) {
-        this(context, attrs, 0);
+        super(context, attrs);
+        setLayoutResource(R.layout.preference_volume_slider);
     }
 
     public VolumeSeekBarPreference(Context context) {
-        this(context, null);
+        super(context);
+        setLayoutResource(R.layout.preference_volume_slider);
     }
 
     public void setStream(int stream) {