Mms: Menu not have some options after tap "Add subject"

In method onPrepareOptionsMenu(),if mms is slideshow,not
add "Insert smiley" and "Import Template" options to menu.

Modify the condition to subject editor is visible or mms
is not slideshow.

CRs-Fixed: BZ1281

Change-Id: I47325fbe9c6bac58933cdaba249c51a3d7283a65