Support listening to events triggered directly on the window

[lazd]

Changes

• matchesRoot has been modified to check if the element is equal to the window
• matchesRoot has been modified to check if the element is equal to document.documentElement
  • This is a more cross-browser compatible way of implementing the check added by @matthew-andrews in 4f0eaa7. I've left the previous commit intact for history's sake.
• assert/refute are explicitly declared now
  • Existing tests were not passing due to both functions being undefined.
  • This is related to Tests do not pass with fresh master #59, but does not fix it entirely as tests still will not pass in PhantomJS

Testing

The following tests were added:

• Delegate instances on window catch events when bubbled from the body
• Delegate instances on window catch events when bubbled from the document
• Delegate instances on window catch events when bubbled from the element
• Delegate instances on window cause events when dispatched directly on window

Tests were ran against the following browsers and are passing

• Safari 7.0.6, OS X 10.9.5
• Chrome 38.0.2125.111, OS X 10.9.5
• Firefox 33.0, OS X 10.9.5
• IE 9.0, Windows 7 Enterprise x64

[lazd]

This was VERY curious. I was getting "Invalid Argument" error in IE 9 when using the assert.calledOnce(spy) statement, but the error went away and the test passed when I used assert(spy.callCount === 1).

Looks like Buster needs better cross-browser testing ;)

[notlee]

This looks good to me @lazd! 5 years later... thanks for the contribution! I've created a PR here with your changes to resolve some conflicts. #102