R21 merge

I suppose I didn't break anything but in case anyone wants to proofread if all our changes are still reflected after this merge - I would highly appreciate that.

Should include:
- ViewPager enhancements for scrolling
- CursorLoader fixes
- LoaderManager checks whether loader is an anonymous class
- BadParcelable in FragmentManager
- SimpleCursorAdapter bugfixes

I created a branch 'upstream' which I aim to push newest vanilla revisions as the appear, so we can easily merge them in the future.