Push app icon 4 dp to the right.

- This makes the icon for AppPreference center aligned.

Change-Id: I2624f376d7637fe49b8bc629e87cb55c3b6271cd
Fixes: 72710732
Test: visual

res/layout/preference_app.xml

@@ -31,6 +31,7 @@
         android:gravity="start|center_vertical"
         android:minWidth="56dp"
         android:orientation="horizontal"
+        android:paddingStart="4dp"
         android:paddingEnd="8dp"
         android:paddingTop="4dp"
         android:paddingBottom="4dp">