[3.0]Add focus indicator only when attaching physicalkeyboard

[3.0]Add focus indicator only when attaching physicalkeyboard

Add focus indicator only when attaching physicalkeyboard.

When user wants to preset focus actor before physicalkeyboard is
attached,
they can call SetCurrentFocusActor().

Before this patch, it always displays focus indicator whether
pyhisicalkeyboard is attached or not.

Now, if pyhisicalkeyboard is not attached, SetCurrentFocusActor() dosen't
add focus indicator to focus actor.

Change-Id: I8a7015279be77c77eb87f2a66346aa5924c76ab5
Signed-off-by: minho.sun <minho.sun@samsung.com>