Update the Manage Storage preference.

Now, it is a master switch preference which can toggle the
automatic management on/off. This also removes the old
UI in the storage summary at the top.

Bug: 33199077
Test: SettingsRoboTests

Change-Id: I709fd2ca0687f760a5d97ad6bebe477b427b0464

src/com/android/settings/deletionhelper/AutomaticStorageManagerSettings.java

@@ -18,6 +18,7 @@ package com.android.settings.deletionhelper;
 
 import android.app.Activity;
 import android.app.AlertDialog;
+import android.app.FragmentManager;
 import android.content.ContentResolver;
 import android.content.Intent;
 import android.os.Bundle;