Show all properties in the Property Editor, even if they are not editable

[johnpryan]

We should show all the available properties in the Property Editor, regardless of whether or not they are editable.

When I select a Container widget in the Property Editor, I don't see all of the attributes like color:

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DevTools version: 2.45.1
IDE: VSCode

[elliette]

This is WAI - see https://docs.flutter.dev/tools/property-editor#editing-widget-properties, we don't support color and object types

[johnpryan]

I'm going to re-open this issue and ask that we show all the properties, regardless of whether they can be edited or not. That way, the user could use the PE to see what's available even if they need to write code to add / edit them.