fix: make overlay display over backdrop, by appending overlay to body

[timblack1]

Fixes PolymerElements/paper-dialog#7
Fixes Polymer/polymer-starter-kit#154
Fixes (maybe) PolymerElements/paper-dialog#79
Fixes (maybe) PolymerElements/paper-dialog#44
Fixes (maybe) PolymerElements/paper-drawer-panel#122
Related to #72
Related to #86
Related to https://github.com/PolymerElements/iron-overlay-behavior/compare/backdrop-refit
Fixes (maybe) PolymerElements/paper-dialog-behavior#78
Fixes PolymerElements/app-layout#155

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[timblack1]

I signed it!

[googlebot]

CLAs look good, thanks!

[valdrinkoshi]

Hi @timblack1, the current proposal has several drawbacks, e.g. it breaks style encapsulation. Also, the fact that you reparent it will cause detach and attach to be triggered, potentially entering in an infinite loop.

[timblack1]

Does https://github.com/PolymerElements/iron-overlay-behavior/blob/master/iron-overlay-backdrop.html#L99 break style encapsulation too? That is the line which necessitates a fix like the one proposed here.

[valdrinkoshi]

Not really, as it is done if you explicitly call the method and if the element doesn't have a parent.
In essence it is suboptimal to attach, detach & attach elsewhere. This would cause query selectors to stop working, it would be a very breaking change.

I'm working on overcoming these stacking context related issues in the stacking-context branch. Happy to discuss the approach in a separate issue!

[timblack1]

I don't see an infinite loop in my manual testing of this proposed change. I look forward to seeing a good resolution of the problem.

[valdrinkoshi]

The PR with the proposal is this one #155
Closing this PR.

[alimd]

its works but its not a good way for solving problem, its like a hack dom, and maybe make problem with data binding, etc ...