[Localization]: Fix ViewLocalizer so it works for layouts too

[kirthik]

ViewLocalizer cannot be used on layout pages since the logic in Contextualize method reads current view to get the resources file. Since ViewContext.View property does not point to layout, layout specific resources are not localized. Today we have to use IStringLocalizer for this scenario.

We should come up with a solution where ViewLocalizer works for layouts too.

[danroth27]

@DamianEdwards

[Eilon]

@DamianEdwards do we want this for beta8? If so, we need to discuss a design.

[dougbu]

Hit this issue while experimenting. For the same reason, localization does not work as expected in _ViewStart.cshtml files e.g. when setting a default ViewData["Message"] value. This breaks componentization and means resources must be repeated for all top-level views.

Suggest ViewLocalizer line 101 should use viewContext.ExecutingFilePath and not the current viewContext.View.Path. The first changes much more frequently.

[Eilon]

Can you clarify? Do you mean that _ViewStart is picking up resources from the real view that's running? If so, I agree that's wrong.

[dougbu]

_ViewStart [and _Layout] is picking up resources from the real view that's running?

Yes, that's what I and @kirthik meant. Fortunately one design (thinking of the Needs Design label) is a one-line fix.

[DamianEdwards]

ViewLocalizer should use ViewContext.ExecutingFilePath when constructing the resource base name