Fix accessibility labels for icon buttons

The icons and frames could get accessibility focus at the same
time previously since we set an onClickListener on the icon though the
icons are not focusable in layout specification. Therefore, we move the
onClickListener to the frames to keep the icons non-focusable.

Bug: 269218388
Test: Manually - add a video and a screenshot to bug
Test: atest SeekBarWithIconButtonsViewTest
Test: atest FontScalingDialogTest
Change-Id: I4ea0fd1efb4f8e84200e211519c5a46309cfb1c0