Make Base ToolButtonStyle honor icon size.
Make Base ToolButtonStyle honor icon size.

Change-Id: Iba7cd88bd3d69ad254f312f57845d10c6170af63
Reviewed-by: Gabriel de Dietrich <57b5c683f0b6abfc17ef151d5b68c8944258b63a@digia.com>

mizukusak/qtquickcontrols,mizukusak/qtquickcontrols,mizukusak/qtquickcontrols