Extend taskbar color to entire screen in overview

Only when taskbar is unstashed in apps:
- Scrim workspace with the taskbar color when opening apps and in BackgroundAppState
- Crop opening apps to above the taskbar
- Crop TaskViews to above the taskbar during gestures

If taskbar is stashed in apps, behavior is the same as before, i.e. no scrim over the wallpaper and no cropping of tasks.

Added a field DeviceProfile#taskbkarPresentInApps to distinguish these cases. LauncherTaskbarUIController and TaskbarStashController ensure this value is set appropriately.

Test: Ensure tasks don't appear behind taskbar when it's unstashed; set ENABLE_SCRIM_FOR_APP_LAUNCH = true to test the whole screen scrimming when opening an app

Bug: 196257194
Fixes: 190681228
Change-Id: I481501457a5a6d49c380feea3db3b4058e4cf3f8