Add tokenCurrency to EuiIcon

[ryankeairns]

Fixes #2395

Summary

Adds generic 'tokenCurrencyglyph toEuiIcon`. The shape is a universal symbol for generic currency.

Preview

Checklist

• Checked in dark mode
• Checked in mobile
• Checked in IE11 and Firefox
• Props have proper autodocs
• Added documentation examples
• Added or updated jest tests
• Checked for breaking changes and labeled appropriately
• Checked for accessibility including keyboard-only and screenreader modes
• A changelog entry exists and is marked appropriately

[ryankeairns]

@snide One thing I've learned is that tokens always have a background color. You can change shape, drop the border, or do a solid fill, but you pick from 1 of 10 tints.

The question now is, do we push forward with tokens in your case and use a background, or do we move this currency glyph to the base icon set and you color it from there as Caroline did for Lens?

[snide]

@ryankeairns I think it's OK to go with tokens. The color doesn't matter as long as they are somewhat qualitative. If we DO go in the tokens route, i think we'll need some tokens for things we have icons for. For example: bringing the globe over for Geo? Cal for Date, Link for URL...etc.

I leave the design call up to you to how you want to handle this stuff and implement whatever you think is best. You might want to check out lens and see what @cchaos is doing over there as well.

[daveyholler]

FWIW, although tokens technically let you put any EuiIcon you want in there, some icons scale a little funny to the smaller size the token uses.

Basically just weighing in that duplication may occasionally be necessary across tokens and icons at the sizes we're currently using. 🙂

[ryankeairns]

Taking that all into account, I think it would be best to use a colored icon (with no background color or shape), so I'm going to move this tokenCurrency icon to a base currency icon so that the data grid work can move forward.

That said, it does seem like we perhaps ought to be using tokens in instances such as this, however that component does not currently support the no-background result that I'm after here.

By moving this icon to the base set, it can still be used by EuiToken down the road. I'll also open a discussion issue about possibly adding this alternate no-background design to EuiToken or handling this in some other fashion (including how we move/duplicate existing icons from base to token and vice-versa).

[snide]

Works for me. Now that it's in the regular icon set, do we care that this is a heavier stroke? Your call. Safe to merge.

[ryankeairns]

Since this a universally known icon, and it follows that design, I'm good with it.

Also, as Davey pointed out, you sometimes have to optimize for the token style which this does (for better or worse at the moment). The thicker style also seems to fit in alongside some of the other token-ish icons (see below), all of which may move and/or be optimized for each set.