Revert "Bring back the status bar activity indicators for mobile data and wifi"

This reverts commit 267eff9f4c0cf4cfd3fb0af3f3e3914c59eb29a4.
Bring back the status bar activity indicators for mobile data and wifi

* adds a setting for this as well as reverting the following commit:

Reverts "Remove signal/wifi activity indicator icon overlays."

This reverts commit fcc901c10bffdfb9c6b31e676dec36b47d949979.

Change-Id: I7aa85f7c8442c45d17e42cac7823dfe93e3f24c1