fix a11y issue where scroll next can still be triggered on final page in

RecentsView

Bug: 151450844
Test: manual verification with following steps
1. launch a few apps
2. swipe up from bottom to bring up RecentsView
3. enable talkback
4. perform a scroll next a11y gesture (without lifting finger, swipe
right then left)
5. verify nothing happens (as opposed to pushing the page back a little)

Change-Id: I6dea2559592bdaa7227a2e12ce0565d6d7b7f4a1