Fixed empty input field

Field may be null, will be uses "0" instead

Change-Id: I2ab7ef6a1f36c718a512a3068ca43b0caa5d5291
1 file changed
tree: 6a53ba1d1dc537e633c9d48c2afad569f1b520b2
  1. org.eclipse.example.calc/
  2. org.eclipse.example.calc.test/
  3. pom.xml