Fix touch interceptions.

We were unfortunately passing through all touches and never intercepting
events from the message ScrollView. This was desirable when the drag was
over the message content, but in the surrounding chrome it would lead to
pressed states while dragging, sometimes accidentally causing text
selection. This change makes that logic special cased to WebViews only.

Bug: 5361173
Change-Id: Icf535c015cec4a79a5ad7eba3d6c5aa7bd572a8a
1 file changed