Make dashboard tile refresh more effcient.

Instead of removing and re-adding all dashboard tiles, figure out a diff
and rebind/add/remove as necessary.

Bug: 32255863
Test: RunSettingsRoboTests
Change-Id: I9d87ba30ab746257d0ea71282951348ebc4e8965

src/com/android/settings/dashboard/DashboardFeatureProvider.java

@@ -15,6 +15,7 @@
  */
 package com.android.settings.dashboard;
 
+import android.content.Context;
 import android.support.v7.preference.Preference;
 
 import com.android.settingslib.drawer.DashboardCategory;
@@ -53,4 +54,10 @@ public interface DashboardFeatureProvider {
      * Returns an unique string key for the tile.
      */
     String getDashboardKeyForTile(Tile tile);
+
+    /**
+     * Returns a {@link ProgressiveDisclosureMixin} for specified fragment.
+     */
+    ProgressiveDisclosureMixin getProgressiveDisclosureMixin(Context context,
+            DashboardFragment fragment);
 }