Use nav frame height to differentiate quick switch vs edge gesture

Originally used shorter nav height in gestural mode. Fix by using
the frame height to make back execute at a higher position compared
to quick switch.

Fixes: 130185782
Bug: 112934365
Test: manual and in landscape
Change-Id: I1befdd4bd35a251926a7d361b4e1cb131e03ded3
2 files changed