Show multiple icons for GroupedTaskView

* Hide all overview actions for GroupedTaskView
* Move some logic from TaskView into respective
PagedOrientationHandlers
* Remove unused methods from PagedOrientationHandler
* NOTE this is just visual changes. Properly showing
task menu's is still in-progress

Bug: 181704764
Test: Tested GroupedTaskView in portrait/landscape,
fake landscape in small screen, and real portrait/landscape
in large screen

Change-Id: I9c13ca114024db0a8e3fa5d295951696adb8516f