[MAYA-126919] Request to use displayColor when disabling "Textured" in the viewport

Hi maya-usd team, happy new year!

I was unsure if this is a bug or a feature request, so I'm logging this as a "Feature request".

**Context**
This relates to the request from https://github.com/Autodesk/maya-usd/issues/2206 to allow a USD Stage to "listen" to the `Textured` control from the viewport toolbar:


**Current Behavior**

With the update from https://github.com/Autodesk/maya-usd/pull/2599, textures get disabled (good) but meshes are drawn with black color instead of drawing according to their `displayColor` property.

This [magazines.zip](https://github.com/Autodesk/maya-usd/files/10340728/magazines.zip) zip file contains the `usdz` stage from `entity/books_magazines01/books_magazines01.usda` from the [ALab phase 2](https://dpel.aswf.io/alab/).

Go to `Create / Universal Scene Description (USD) / Stage From File...` and select the zip file. You can see how toggling the `Textured` button goes from textured geometry to black geometry:


When loading the complete ALab set, the same happens:


**Expected Behavior**

USDView and Houdini respect `displayColor` when disabling scene materials, which is why as a user, I would expect for Maya to do the same. In the ALab example, we can see that meshes which did not have a material previously applied, continue to draw with `displayColor`:


USDView exposes this with the `Enable Scene Materials` menu:



Houdini does it with the `Display Materials on Objects` toggle:


Could the Maya `Textured` toggle follow the same approach?

Thanks!