Revert^2 "Re-adding logic to hide launcher shortcuts when shade is open"

This reverts commit 50aaabe4.

Reason for revert: Comment #18 on b/315576239 confirms the forward fix mitigated the original regression; hence this revert was unnecessary and should be undone to prevent the original issue b/267465887 from regressing.
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:b4d4604a9b618d20971787196d8839fef9b32d0c)
Merged-In: If9e0aebba47a7778a7f6a7c32c83fedb281d9603
Change-Id: If9e0aebba47a7778a7f6a7c32c83fedb281d9603