Add MediaProjection privacy item type

Active MediaProjection cannot be tracked using AppOps,
instead this uses MediaProjectionManager callbacks to track the
corresponding new PrivacyType.

Bug: 184629645
Test: atest AppOpsPrivacyItemMonitorTest PrivacyItemControllerTest PrivacyConfigFlagsTest
Test: m SystemUI CarSystemUI ArcSystemUI
Test: Manual on TV, observe media projection privacy indicator
Change-Id: I8924ebb7871da432b0e4e49c465a0c43e515ca4b
Merged-In: I8924ebb7871da432b0e4e49c465a0c43e515ca4b