Update split handle touch target size

This CL updates split devider handle region specs, which is used to calculate the touch target position and size. The region is set to 48*80, or 80*24 in portrait desktop mode to avoid colliding with the app handle.

Bug: 338079912
Test: Manually
Flag: EXEMPT bugfix
Change-Id: Ibbf653e670ab6e481ed92e21fad775fb3a922d32
2 files changed