Stash taskbar when software keyboard is docked

Stash taskbar when
1) Software keybaord is docked
2) Input toolbar is placed at the taskbar area (stash so toolbar and taskbar would not overlap)

Testing result:
https://drive.google.com/file/d/1NMDexHl0FgyHFaOUh_GSEEUU2k08STJH/view?usp=sharing

Bug: 317251202
Test: TaplTestsQuickstep#testQuickSwitchToPreviousAppForTablet
Flag: N/A

Change-Id: I90662bc6e68f644e919f5c702059476b02519ed6