Handle screen capture disabled state for multiple users

Before this fix, the framework use one single integer to track screen
capture disabled policy across the device. This can be either a real
userId, or the symbolic USER_ALL or USER_NULL for all users or no user.
This has the problem that it can't represent policies from more than
one admin (or policies from both the admin and its parent). In addition,
due to the way DevicePolicyManagerService refreshes policies, when a
non-managed user is started, its default policy state overrides any
existing policy, causing screen capture to be no longer disabled.

Fix this by properly tracking the policy for each user in an set.
We still use USER_ALL in the set to represent screen capture being
disabled for all users.

In Android 14, the screen capture logic is migrated to policy engine
which already contains this fix.

Bug: 305664128
Test: ScreenCaptureDisabledTest
Test: FrameworksServicesTests:DevicePolicyManagerTest
Test: DevicePolicyManagerServiceMigrationTest
Test: MixedDeviceOwnerTest#testScreenCaptureDisabled_assist
      MixedProfileOwnerTest#testScreenCaptureDisabled_assist
      MixedManagedProfileOwnerTest#testScreenCaptureDisabled_assist
Test: MixedManagedProfileOwnerTest#testScreenCaptureDisabled_assist_allowedPrimaryUser
Test: MixedDeviceOwnerTest#testCreateAdminSupportIntent
      MixedProfileOwnerTest#testCreateAdminSupportIntent
      MixedManagedProfileOwnerTest#testCreateAdminSupportIntent
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:5f3db5ae9b9cf69c8a4ea73b6ed49ce9d49ba223)
Merged-In: Ib016b740927003f8bd81992f24c722c29ac723b5
Change-Id: Ib016b740927003f8bd81992f24c722c29ac723b5