Remove unused strings

    <string name="actionbar_selected"><xliff:g id="selection_count">%d</xliff:g> selected</string>

    <string name="next_action">Next</string>

    <string name="previous_action">Previous</string>

    <!-- Used to confirm acceptance of dialog boxes, warnings, errors, etc. -->

    <string name="okay_action">OK</string>

    <string name="cancel_action">Cancel</string>

    <string name="message_view_sender_label">via %1$s</string>

    <string name="from_same_sender">More from this sender</string>

    <string name="search_from_format">From <xliff:g id="sender">%s</xliff:g></string>

    <string name="message_discarded_toast">Message discarded</string>

    <string name="message_saved_toast">Message saved as draft</string>