Crash when invoking .count() on an empty results

[nirinchev]

When you construct an empty (unbacked) results instance (

realm-core/src/realm/object-store/results.hpp

Lines 211 to 214 in ea7b5d3

	// A default-constructed Results which is backed by nothing. This
	// behaves as if it was backed by an empty table/collection, and is
	// inteded for read-only Realms which are missing tables.
	Empty,

) and then invoke count on the query obtained from the results, we get a crash when trying to obtain the logger in

realm-core/src/realm/query.cpp

Line 1390 in ea7b5d3

auto logger = m_table->get_logger();

.

The test I have is a C# one, but it roughly does:

Results = {};
results.set_update_policy(Results::UpdatePolicy::Never);

results.get_query().count(results.get_descriptor_ordering());