Rely solely on new URL for link control url validation

[jeryj]

What?

1. In Add URL validation in LinkControl using ValidatedInputControl #73486 we said we were relying on new URL to validate URLs, but this isn't entirely true. We are using isURLLike to filter out some URLs that would pass the new URL constructor (URLs with spaces, for example, get converted to %20) and we also allow hash links and fragments to skip the new URL check. Not only that, but we call hash links with duplicate # invalid, but new URL passes these and it does technically work.

2. I noticed that prependHTTPS's flow is to prependHTTP then replace http with https. Since we're defaulting to https more, the easiest way to improve this is to switch that. Have prependHTTP rely on replacing https with http.

Why?

I'm not sure this is the right direction, but wanted to open the discussion to get consistency.

How?

Rely solely on new URL for consistency.

Testing Instructions

Testing Instructions for Keyboard

Screenshots or screencast

Before	After

[jeryj]

@getdave - not a priority but what are your thoughts?