Fix unintended scroll in all apps when using external mouse.

The reason is because when ag/29152694 was introduced, the accessibilityEvent that would
trigger is TYPE_VIEW_HOVER_ENTER that would eventually always have the list scrolling depending
on where the mouse would be. Gating it to TYPE_VIEW_ACCESSIBILITY_FOCUSED would be fix this as
this should still work for talkback when traversing the A-Z list as TYPE_VIEW_ACCESSIBILITY_FOCUSED is whats is always used
during this case.

bug: 372965379
Test: manually
Flag: EXEMPT bug fix
Change-Id: I249cee8036216f93aab53efc3d77fad047f7e408