angular: [elements]: custom element inside a custom element's template throw on destruction

I’m submitting a…

[ ] Regression (a behavior that used to work and stopped working in a new release)
[x] Bug report  
[ ] Performance issue
[ ] Feature request
[ ] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead see https://github.com/angular/angular/blob/master/CONTRIBUTING.md#question
[ ] Other... Please describe:

Current behavior

We have 3 custom elements, A , B and C - All are angular components converted to custom elements.

We create a new A programatically, with an injector.

Inside A we append HTML code, the code includes markup that will create B. (B doesn’t have an injector).

In B’s template, we have markup to create C.

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Stopping here to point out that while C is inside an angular template markup and it is an angular component, the fact that it’s declared as a custom element means that it will be handled by @angular/elements.

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Now, A was created programatically so we have a reference for it.
We remove it (NgElement.remove()) which starts the destruction process.

When @angular/elements starts the destruction process and error is thrown:

ERROR TypeError: Cannot read property ‘nativeNode’ of null

at removeDebugNodeFromIndex (core.js:5407) at DebugRenderer2.push.../../node_modules/@angular/core/fesm5/core.js.DebugRenderer2.destroyNode (core.js:11398) at destroyViewNodes (core.js:10613) at destroyView (core.js:10601) at callWithDebugContext (core.js:11351) at Object.debugDestroyView [as destroyView] (core.js:11035) at ViewRef_.push.../../node_modules/@angular/core/fesm5/core.js.ViewRef_.destroy (core.js:8868) at ComponentRef_.push.../../node_modules/@angular/core/fesm5/core.js.ComponentRef_.destroy (core.js:8705) at elements.js:236 at ZoneDelegate.push.../../node_modules/zone.js/dist/zone.js.ZoneDelegate.invokeTask (zone.js:421)

The error happens when @anguar/core try’s to destory C.

What happens is that DebugRenderer2.destroyNode() is called TWICE for C. My guess is that because C is a custom element used inside an angular template both angular and angular/elements invoke a destroy… something like that I guess.

Expected behavior

Should not throw…

It’s worth noting that even if I disable the delay of destruction it stlll throws