Icon titles don't show as tooltips

[invliD]

Steps to reproduce

1. <Icon icon="error" title="No good!" />

Actual behavior

The title is not shown in a tooltip

Expected behavior

The title is shown as a browser tooltip, like any other element's title prop

Possible solution

Put the title on the span around the icon, not in a desc element inside the icon.

The current purpose of title seems to be what should be called alt

[giladgray]

little context here: #2321, #2410. the original browser tooltip behavior was very obnoxious because every icon would get a browser tooltip, so i switched the SVG element to one that provides the same a11y but doesn't show a tooltip.

i see valid uses for occasional browser tooltips, but it can't be the default behavior.

given that, we can't repurpose the existing title prop as that would be an API break (per the docs: "This string does not appear in normal browsers...").

@invliD @gabeboning how about adding an htmlTitle prop that sets title on the wrapper DOM element? in v4 we can switch the names around.

[giladgray]

fixed in #3216