1. The AccessibilityInteractionController was using an incorrect
looper i.e. not the UI thread looper which was causing getting
the root node to fail.
2. The AccessibilityNodeInfo was populated by a ViewGroup with the
children for accessibility without checking whether these children
are really displayed.
bug:6362875
Change-Id: I7906d89571eb9d57d10f971639f88632926dd077