[sailfish-browser] Add input item size and zoom margin perferences. Contributes to JB#8462
[sailfish-browser] Add input item size and zoom margin perferences. Contributes to JB#8462

sailfishos/sailfish-browser,sailfishos/sailfish-browser,sailfishos/sailfish-browser,alinelena/sailfish-browser,alinelena/sailfish-browser,alinelena/sailfish-browser,sailfishos/sailfish-browser,rojkov/sailfish-browser,alinelena/sailfish-browser,rojkov/sailfish-browser,sailfishos/sailfish-browser,rojkov/sailfish-browser