1322599 - [geckoview] Use abstract classes for delegates instead of interfaces

Status: RESOLVED INVALID

(GeckoView :: General, defect, P3)

Description

[James Willcox (:snorp) ([e-mail]) (he/him)]

Or at the least, we should offer abstract classes that implement the current interfaces and have base functionality that makes sense. The benefit is that often you only want to implement some of the interface and not the whole thing, so this makes that convenient.

Comment 1

[Nick Alexander :nalexander [he/him]]

(In reply to James Willcox (:snorp) ([e-mail]) from comment #0)
> Or at the least, we should offer abstract classes that implement the current
> interfaces and have base functionality that makes sense. The benefit is that
> often you only want to implement some of the interface and not the whole
> thing, so this makes that convenient.

One counter-argument: you often end up with `CanonicalNameDelegate` and `CanonicalNameDelegate2` when you want to version or improve things.  I'm gently against this approach, because I think it contradicts the general strength of "prefer composition over inheritance".

Comment 2

[[ex-Mozilla] Agi Sferro | :agi]

We now have enforced default impl in every delegate interface, so this is not needed anymore.