Allow to search related field in search box
This is a frequent request to be able to use the dotted notation in the search box.
The problem is that the domain parser needs to know the definition of all the related field. As this is not possible, I propose to put a limit to the level of "nesting".
So the idea is that the fields_view_get returns for tree view, the fields in the definition of each relational field. This extra definition will be used by the parser to parse/complete/format the domain clause using dotted notation.
As it can be expensive to provide those definitions, I propose to limit by default to only 1 level. Developers may customize it for specific model.