Add sensitive content protection during screen share

If a view is deemed sensitive either by system heuristics
or explicitly set by the developer, The window would
be blocked from being projected (screen share) until
it has a sensitive view attached.

Bug: 324348549
Test: CtsSensitiveContentProtectionTestCases
Change-Id: I22abdbe487793e88b6ab6375f6a1f2e1f3407b03