Fix TYPE_VIEW_SCROLLED event in AsListView and ListView

We should always send TYPE_VIEW_SCROLLED event when scroll. This applies
to ACTION_SHOW_ON_SCREEN. And we also need the scroll event when the
first visible item and last visibile item don't change.

Fix: 147907655, 147282475

Test: tested b/147282475 is fixed (this bug is not related to
ACTION_SHOW_ON_SCREEN, it is the scroll forward action).

Change-Id: I2069dc3ee692042ff87867db9837e85ac1d8dd26