Revert "Partial Screenshare Opt-Out Override"

Revert submission 25896593-partial-screenshare-override

Reason for revert: b/326596442, b/325883822, b/325772966, b/325503599, b/325448962, b/325155886, b/325091205

Reverted changes: /q/submissionid:25896593-partial-screenshare-override

Fixes: 326596442
Fixes: 325883822
Fixes: 325772966
Fixes: 325503599
Fixes: 325448962
Fixes: 325155886
Fixes: 325091205
Change-Id: I29979b30cbc8e435b3492cf8269dd0eec2f87cb0