Fixes for Geocoder when hosted via web components

[mramato]

The Geocoder suggestion box does not currently work if hosted inside of a web component. I tracked it down to the use of container.contains(e.target) in _onInputBegin. Because of the shadow DOM, this check always evaluates to false inside of web components and search suggestions are never shown.

I'm not sure it's possible to make container.contains(e.target) work in a web components the way we were relying on it, but the entire thing way we were handling this seemed a little convoluted to begin with so I removed the use of document pointer/mouse events and made it use standard blur/focus events instead. As far as I can tell behavior is identical but now the code should be more portable.

[cesium-concierge]

Thanks for the pull request @mramato!

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Reviewers, don't forget to make sure that:

• Cesium Viewer works.
• Works in 2D/CV.
• Works (or fails gracefully) in IE11.

[hpinkos]

@mramato clicking the autocomplete results appears to be broken?

[mramato]

@mramato clicking the autocomplete results appears to be broken?

Damn it, I thought I fixed that. The problem is that blur is processed before click so clicking on the suggestion hides the box and then the click doesn't happen. I had a settimeout in there to fix it which worked for me but I'm guessing it's not a good enough fix. I'll see if I can find another way.

[mramato]

@hpinkos I had to bail on my initial approach because of the impossibility of handling a click after blur for the same element. Instead, I figured out a way to make e.target and node.contains work in the shadow DOM. Here's the new approach:

Geocoder was relying on Event.target which does not work with the Shadow DOM. This prevented suggestions from appearing inside of web components. Detect if shadow DOM is being used and access the composedPath to retrieve the real target if so.

Also remove unnecessary contains check for onInputEnd because we can just listen subscribe to the container itself rather than the entire document.

[hpinkos]

👍 works great, thanks @mramato!