Revert "Allow views to setSystemUiVisibility() with the same value and have it work."
Revert "Allow views to setSystemUiVisibility() with the same value and have it work."

This reverts commit fad9555217ce3a657ffc7cba458a0d2622f7a379.
Because it just didn't work. (The views kept aggressively
re-applying their preferred flags every time view attributes
were aggregated.)

We'll pursue the original strategy, like lights out mode in
HC: if you want to tickle this mode, un-set and re-set the
flags (preferably synchronized with the global SystemUI
visibility state as reported by onSystemUiVisibilityChanged
callbacks).

Bug: 5052456

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base