Return empty cursor when work profile is disabled.

Currently we return empty cursor for cross-profile calendar uris if:
1. work profile does not exist
2. user turned setting off
3. calling package not allowed by admin

But we return null if: work profile exists but is disabled.
This is somehow inconsistent with the other behavior and could
potentially cause crashes for apps that are not careful with
the implementation.

Bug: 126370740
Test: atest ManagedProfileTest#testCrossProfileCalendar
Change-Id: I9a4a4a287296e7c51c6635ac99c42da558dc0ccc
1 file changed