Fix phpdoc and tests for NamingStrategy

[greg0ire]

While working on #9758, I noticed 2 things that need to be fixed.

When computing a foreign key column name, the referenced column name
may be null in the case of a self referencing entity with join columns
defined in the mapping. I wrongly introduced that phpdoc in #9756.
Also, some tests were using the fact that some arguments of some methods of
the naming strategy interface are optional or nullable for now to avoid
providing some. In practice, these arguments are always provided, and
that should also be the case in tests.

For propertyToColumnName, I think ClassMetadataInfo::$name is always a non-nullable string
See

orm/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php

Line 1635 in 45e196e

$mapping['columnName'] = $this->namingStrategy->propertyToColumnName($mapping['fieldName'], $this->name);

For joinTableName() I think related mapping are always defined based on some property and cannot be null either.

orm/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php

Line 2050 in 45e196e

$mapping['joinTable']['name'] = $this->namingStrategy->joinTableName($mapping['sourceEntity'], $mapping['targetEntity'], $mapping['fieldName']);

[SenseException]

I wrongly introduced that phpdoc in #9756.

I didn't realized that either.

[greg0ire]

I didn't realized that either.

Yeah I think it's hard to realize until you actually conduct the actual breaking change on the next major branch 🙂