Fix x/y translation misses from ViewPager.java

[journeymansix]

I found a couple of places where the translation from x to y was apparently missed in the copy/modify from ViewPager.java. I also updated a couple of code comments similarly. Lastly, I removed the cast to (View) in debugging statements, which was causing invalid cast errors for me, and apparently isn't necessary.

[squallstar]

any chance we can get this merged in?

[ninovanhooff]

@castorflex Please do merge this and update the aar @ jcenter. Thanks!