ValidateFileUsage does not seem to pick up img src and deletes image files actually being used

There are two issues here, both related to the generated queries.

First is, that the module generates one query per entity type and adds _all_ eligible fields from _all_ available bundles. However, the table JOIN is INNER and thus it could only work like that on bundles that contain _all_ WYSIWYG fields. This should be changed to LEFT JOIN.

Secondly, the WHERE clause also checks _all_ eligible fields of that entity type and concats them with AND. This should be changed to OR.

With both of these changes in SQL, I was able to correctly find occurrences of my unmanaged files.

The culprit is in the usage of orConditionGroup(). The attached patch fixes that.