Reimplement inline link-to as an AST transform

[mmun]

I also had to fix broken tests that didn't pass enough arguments to link-to because they were triggering an assertion that params.length > 0.

[mmun]

Hmm, this strategy doesn't work with custom link-tos. Might just close this.

[rwjblue]

I think that it is fine that the inline form is specifically for {{link-to}} and not for custom versions of link-to.

[rwjblue]

@mmun - This needs a rebase and some updates when you have a minute.

[nathanhammond]

This is only marginally different from the current state with extending the link-to component. If you need to modify qualifiedRouteName or willRender you lose the ability to have an extended inline link-to because you don't have a reference to the HAS_BLOCK symbol. Those two will, of course, be the primary places people want to make changes.

I'm in favor of implementing this as an AST transform even with the knowledge that it does make it a bit more magical. (I don't imagine that most people using Ember expect that the code they write is going to be modified like this before it runs which may confuse somebody's debugging session.)

@mmun you want to bring this home, or for me to adopt it?

[mmun]

@nathanhammond Sure, feel free to adopt! :)

[mmun]

I've given you access to my fork of ember.js if you'd prefer to rebase this branch.

[stefanpenner]

Just a side-thought, we may need to make the AST, or atleast the transforms/reducers be part of the public API at some point. I have seen a trend, of really cool things being implemented as AST transforms, but it does worry might slightly due to the potential instability.

I am not saying, we need to drop everything at finalize this, but we explore what it would take.

[nathanhammond]

Ready for review and possible landing. :)

[rwjblue]

Rebased again. Gonna land when 🍏....