This is a reworked submission of #7686 which has been reverted. This series
fixes some race conditions in MV/SI schema creation and load, we spotted some
places where a schema without a base table reference can sneak into the
registry. This can cause to an unrecoverable error since write commands with
those schemas can't be issued from other nodes. Most of those cases can occur on
2 main and uncommon cases, in a mixed cluster (during an upgrade) and in a small
window after a view or base table altering.
Fixes#7709Closes#8091
* github.com:scylladb/scylla:
database: Fix view schemas in place when loading
global_schema_ptr: add support for view's base table
materialized views: create view schemas with proper base table reference.
materialized views: Extract fix legacy schema into its own logic
(cherry picked from commit d473bc9b06)
8f37924694