Theme Override container cannot be used to override layout paddings

[dweymouth]

Checklist

• [X] I have searched the issue tracker for open issues that relate to the same problem, before opening a new one.
• [X] This issue only relates to a single bug. I will open new issues for any other problems.

Describe the bug

The standard layouts all use the deprecated theme.Padding() to look up the padding value which does not pick up the overrides if the layout is used in a container or internally within a widget in an override container.

How to reproduce

create a theme override container with a theme that overrides padding, and put a container with a layout inside that theme override container

Screenshots

No response

Example code

it's trivial from a code audit of the layout package to see where the problem is

Fyne version

2.5.0

Go compiler version

n/a

Operating system and version

all

Additional Information

No response

[andydotxyz]

I think the only way this can be completely resolved is with changes to how the draw is threaded or with an API change for layouts as they have no access to the widget / container that they are being used to lay out.