SelectionController::OnMouse{Up,Move,Down} have broken signatures

SelectionController::OnMouse{Up,Move,Down} have broken signatures

In all three methods, names are misleading.
Patch does the following:

- OnMouseDown -> HandleDragBeginNotification
- OnMoveMove -> HandleDragUpdateNotification
- OnMouseUp -> HandleDragEndNotification

Additionally, patch removes an unused parameter
in all three methods.

Original beta/m42 patch:
- http://165.213.202.130/gerrit/87893 , reviewed by
Hyunhak Kim, arno renevier.

Bug: http://107.108.218.239/bugzilla/show_bug.cgi?id=14304

Reviewed by: a.renevier, j.majnert, sns.park

Change-Id: Iea48026c242bdde6f65c0782369f30d5dadc233a
Signed-off-by: Antonio Gomes <a1.gomes@samsung.com>