New scroll-to modifier

[ygongdev]

Description
Adding a new scroll-to functional modifier that mimics the native scrollTo.
It is possible that we only want to perform a scroll-to if a certain condition is satisfied, so this modifier will optionally take a boolean to know when to trigger its scroll-to

API
The arguments are chosen to closely mimc the API of the native scrollTo, which supports 2 positional arguments or a named option. We just add one more API to support the optional boolean.

Positional arguments: [top, left, shouldScroll] or scrollOptions
Named arguments: { top, left, behavior, shouldScroll }

Examples
Debating between explicit positional arguments and a single positional object containing the config, which gives more flexibility if the native scrollOptions API happens to change.

<div {{scroll-to 100 100 true}}></div>

vs

<div {{scroll-to scrollOptions true}}></div>

Named

<div {{scroll-to top=this.top left=this.left behavior=this.behavior shouldScroll=this.shouldScroll}}></div>

[elwayman02]

Instead of a boolean, how about a Promise? We can execute the scrollTo behavior when that Promise resolves, which can be done programmatically as easy as flipping a boolean flag.

As for argument style, I prefer named but also think we should stick with the options object, like so:

<div {{scroll-to options=this.scrollOptions shouldScroll=this.scrollPromise}}></div>

I would rather support the full, easiest API rather than have to mimic each and every param, and like you said, it's more future-proof. It's easy to define an inline hash in the template if people want to do it that way, as well.

[ygongdev]

Sounds good, I should adapt similar API for the others as well

[ygongdev]

@elwayman02 Oh I just realized the difference between window.scrollTo and element.scrollTo. I think element.scrollTo is meant for within a scrollable element, which is one use case.

If our intention is to scroll to this element, we should be either be using a scrollIntoView modifier or using window.scrollTo and change API to take relative offset values instead of absolute coordinates, so we can take advantage of this.element?