[DO NOT MERGE] Revert "[Security Report] Fix Settings WifiScanModeActivity Overlaid issue"

This reverts commit 32d5d3a3a34fae28410a77b058f75371d15019e6.

Bug: 174047492
Reason for revert:
Look like the WindowManager.LayoutParams.SYSTEM_FLAG_HIDE_NON_SYSTEM_OVERLAY_WINDOWS system flag is not supported in the pi-dev branch.

Change-Id: Iec3c28e8c148f83fc171d696b2fc67f359d03eb8
1 file changed