Change list

I saw some issue reports where people complain about NPE while the driver instance, which is passed as the constructor argument, equals to null. This fix allows to detect the problem on the early stage.

Types of changes

• No changes in production code.
• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)