[TextInputLayout] Ability to set background color for helper texts

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**Is your feature request related to a problem? Please describe.**
Sometimes error text doesn't fare well with dark backgrounds of the TextInputLayout, like in this image.

**Describe the solution you'd like**
So it would be nice to have a way to customize the background of the indicator so that we can avoid this issue. Like an `boxBackgroundErrorColor` attribute.

E.g.

**Describe alternatives you've considered**
I achieved that behavior through a hacky implementation where I findViewById the error text helper and get the parent of it and set the background to the desired color.
```
val emailTextView = binding.emailContainer.findViewById(R.id.textinput_error)

(emailTextView.parent.parent as ViewGroup).setBackgroundColor(Color.parseColor("#FCEEEE"))
```

But as I said it is a hacky and fragile implementation as it would easily break if the implementation details of the Helper Text changes.

Start with TextInputLayout and the textinput_error helper referenced in the issue, including how the helper's parent background is currently reached. Define the supported customization point for the indicator background and verify that the configured color is applied to helper and error text without relying on the internal view hierarchy.

Written by the indexing model from the issue text.