Show a preview of the selected font size immediately

Modified the font size preference dialog to show the user the selected
font size immediately. Also split the size description and percentage on
their own lines to show a preview of two different font sizes. In
addition, removed the gigantic title bar from the dialog.

Change-Id: Ifc1e930f9420bde0bb6fd61b1a395c3d36b4fb0b
Merge "Show a preview of the selected font size immediately" into cm-10.2