schema pointers can be obtained from two distinct entities,
one is the database, those schema are obtained from the table
objects and the other is from the schema registry.
When a schema or a new schema is attached to a table object that
represents a base table for views, all of the corresponding attached
view schemas are guarantied to have their base info in sync.
However if an older schema is inserted into the registry by the
migratrion manager i.e loaded from other node, it will be
missing this info.
This becomes a problem when this schema is published through the
schema registry as it can be obtained for an obsolete read command
for example and then eventually cause a segmentation fault by null
dereferencing the _base_info ptr.
Refs #7420
06cfc63c59