Allow to overwrite contrast color in palette

I want to be able to also overwrite the contrast color for a color palette. Like I can define the primary and the accent color, I also want to be able to set the contrast color.

For example: I have a green navbar with some icons on it. And because my color palette is dynamic (multiple predefined colors), I want to use contrast. But when I use contrast, the icons are black:

So just like primary, I want to be able to set my own contrast color.

const theme = createMuiTheme({
  palette: {
    primary: green,
    secondary: orange,
    contrast: white,
  },
});

[ValentinH]

The contrastText is only used for contrast buttons. This is a bit misleading as I would expect the following example to display a button with white text: https://codesandbox.io/s/9l0109n94p

I guess this is what @TheZoker was asking initially.

[ValentinH]

Done: #9913