B/C Break

When integrating the Framework Application package, we removed the constructor from JApplicationBase to just use the parent Joomla\Application\AbstractApplication constructor. However, the Framework class doesn't allow the CMS's JInput object to be injected since it doesn't extend Joomla\Input\Input. So for anyone who was directly extending JApplicationBase with a custom application class and was injecting a JInput object, this was broken. I've probably got better odds of winning the lotto than that having actually happened, and it would never be noticed because JApplicationWeb and JApplicationCli never call the parent constructors to set the data that would have made this noticeable. If it weren't for me playing with tests, nobody would've known or cared.

JApplicationBaseTest Refactoring

This splits up the tests into more isolated test methods to properly test a single method or behavior per test. Also it uses more mocking of objects than before and the actual application API, cutting some of the dependency on using Reflection to inject things and leaves little dependency on calling either JFactory or JEventDispatcher except where explicitly intended to do so.