ve.ui.Toolbar: Optimise onSurfaceViewKeyUp performance

Follows-up 1b9c077b83.

* Only run expensive height(), offset(), etc. when the toolbar
  is floating.

* Set the property directly instead of using "animate(, 0)".

Change-Id: Ia17f5a3e701a58537df341b7aafd6273b649d4e8
Merge "ve.ui.Toolbar: Optimise onSurfaceViewKeyUp performance"