Restore non-scrolling UI on long screenshots crash

If the long screenshot capture process crashes, or the returned
long screenshot is of height zero, just restore the regular UI
(without the scroll button) and reset the timeout.

Bug: 189331695
Fix: 189331695
Test: manual
Change-Id: Icb9bc230a7151726865715722de0b670f8bf6ffb
2 files changed