Ensure that floating windows on Wear can be non-fullscreen

By default wear uses fullscreen UI experiences, and certainly
by virtue of the default themes on Wear even floating windows
are generally accompanied with fullscreen however it should be
*possible* to override this and allow developers to create a
non-fullscreen experience if explicitly directed via theming.

This is evident in expectations around CtsWindowManagerDeviceAnimation
tests.

Bug: b/338534521
Test: atest CtsWindowManagerDeviceAnimations:MoveAnimationTests
      atest CtsWindowManagerDeviceAnimations:BlurTests

Flag: NONE not required - localized to floating window
      specifically on Wear.
Change-Id: I9c8ab92f68fc0ca651f56d630b3dc8086c6ce314