Workarounds to avoid removing all prefs

Removing all prefs causes ugly animations, so avoid it at all cost
and cache all the prefs (while still added) as long as possible.

Bug: 26271353
Change-Id: I33b84d751938b460f4b66c0158057407dd45d974

src/com/android/settings/bluetooth/BluetoothDevicePreference.java

@@ -84,6 +84,10 @@ public final class BluetoothDevicePreference extends Preference implements
         onDeviceAttributesChanged();
     }
 
+    void rebind() {
+        notifyChanged();
+    }
+
     CachedBluetoothDevice getCachedDevice() {
         return mCachedDevice;
     }