Implement flexible popup depend on text length

Implement flexible popup depend on text length

[Issue#]   P130927-03499
[Problem]  Layout of permission popup is broken
[Cause]    Current WRT doesn't set padding area to popup layout.
           Before it is working fine with default padding supported by elementary,
           the latest version has no padding area is supported.
[Solution] Change popup layout to use padding area.
           - Add padding(SPACER type) between contents and four sides of a popup.
           - Contents area(body text) removes minimum size. (Automatically set by elementary)
           Add scroller if text is overflown screen height.
           - Register "resize" callback to popup.
           - When callback is called, calculate screen height and popup height.
           - In case of popup height is over screen height, add scroller to popup.

[SCMRequest] N/A

Change-Id: Ic07a3209ebeebad0ac35bbab92aea1d5250b31f4