Adjusted magnifier position properly in case that touched position is outside of...

Adjusted magnifier position properly in case that touched position is outside of the editor box.

[Title] Adjusted magnifier position properly in case that touched position is outside of the editor box.
[Issue#] N_SE-40154, N_SE-38039
[Problem] When touched position is outside of the editor box,
          magnifier is displayed in the center of the editor box.
[Cause] Magnifier position is set to the center of the editor box
        in case that touched position is outside of the editor box.
[Solution] Adjusted magnifier position properly like below:
            - If Y of the touched position < Y of the editor box, set to Y of the editor box.
            - If Y of the touched position > maxY of the editor box, set to maxY of the editor box.

Change-Id: I33059e7971915f56192bc00727ec10dfe8e2a0c6