Adjusted padding of buttons (depends on font-size now)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34287 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Typecast fix

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34288 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
#3392 row selection from code. !str.isEmpty()-s are  replaced to "".equals(str).

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34289 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e