Summary

In several places we are throwing Write Conflict Exception for scenarios where the 'collection namespace is already in use'. Those are unrelated to storage engine Write Conflicts. We should use a different error code and handling policy on those situations.

• collection_catalog.cpp::_ensureNamespaceDoesNotExist (here, here and here)
• database_impl.cpp::_checkCanCreateCollection (here) and corresponding checkpoint (here)
• database_impl.cpp::_createCollection (here)