(impact:high) [WidgetObject] internalFactory can be confusing

[juanmendes]

Prerequisites

[Check these off before submitting an issue].

• Are you running the latest version?
• Did you perform a basic issue search?

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Description

WidgetObject#internalFactory has caused confusion for developers. This causes a different way to interact with components depending on whether you're inside a WidgetObject or you're with a test (stepdef or unit test). To avoid this confusion, we should always expose WidgetObjectElements and callers can call unwrap() on their own if they want to use the T functionality that is specific to the testing framework being used.

This also avoids having a private and a public version of a method where the only difference is that the public one calls unwrap().

Impact

This is a breaking change, but we're the only users of this feature and I will update our internal vcd_ui app when this is finished.