Accessibilty: Cannot click on views in a scrollable container covered by the toolbar.

In accessibility mode we calculate a point where to click in the accessibility
focused view as a bridge-gap solution before switching to accessibility click
actions. We cannot detect whether a view is covered by another one that consumes
all touch events, and therefore we may click on the wrong target. This was the
case with the toolbar. As a result a partially scrolled view in a scrollable
container covered by a toolbar cannot be activated and this is not an edge case.

bug:18986806

Change-Id: Ib41470c39806cec13e9b00b319879cd7f3412ab5