Revert "Keep FLAG_SHOW_WALLPAPER flag on NotificationShade."

This reverts commit 7f1a5a79d136fd5c8aa5a0d600cf759eddc09b05.

Reason for revert: Droidfood blocking bugs bug: 203025772 & bug: 203041994 

Change-Id: Iecb089045525e24b5e5ece312016eb20400da575
(cherry picked from commit d28057215b8927440169f2070a5c84ec9b6ac480)
11 files changed