Fixes exceptions like this:
java.lang.NullPointerException: Attempt to read from field 'java.lang.String com.android.mail.providers.Folder.name' on a null object reference
at com.android.email.activity.setup.MailboxSettings$MailboxSettingsFolderLoaderCallbacks.getHierarchicalFolder(MailboxSettings.java:377)
Change-Id: I2c5dda84439caa5d894f5706c9c6a07079cda69c