feat(input): add color prop support

[liamdebeasi]

Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
  • Some docs updates need to be made in the ionic-docs repo, in a separate PR. See the contributing guide for details.
• Build (npm run build) was run locally and any changes were pushed
• Lint (npm run lint) has passed locally and any fixes were made for failures

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Developers using the new input syntax do not have a way of using the Ionic theme to apply a particular theme to ion-input.

What is the new behavior?

• Add support for using the color prop as per the design document

Does this introduce a breaking change?

• Yes
• No

Other information

[sean-perkins]

A few screenshot captures have the label cropped, e.g.:

• core/src/components/input/test/color/input.e2e.ts-snapshots/input-outline-color-floating-md-ltr-Mobile-Chrome-linux.png
• core/src/components/input/test/color/input.e2e.ts-snapshots/input-outline-color-floating-md-ltr-Mobile-Firefox-linux.png
• core/src/components/input/test/color/input.e2e.ts-snapshots/input-outline-color-floating-md-ltr-Mobile-Safari-linux.png
• core/src/components/input/test/color/input.e2e.ts-snapshots/input-outline-color-stacked-md-ltr-Mobile-Chrome-linux.png

This is likely because the input bounding box does not contain the translated label for these displays.

[averyjohnston]

I'm not seeing the colors when running the test locally on Chrome (screenshot), should I be?

[liamdebeasi]

The colors only apply when focusing the input as per the MD spec: https://m2.material.io/components/text-fields

[liamdebeasi]

@sean-perkins Do you want me to add top padding to the MD screenshots? I'm not sure how much additional information we would gain by adding it though.

[sean-perkins]

I think we are good as-is, as long as the screenshot capture is consistent. We can re-evaluate in the future if it becomes a problem.