Update detectElementResize to support rendering into iframes and child windows#900

Merged

bvaughn merged 2 commits intobvaughn:masterfrom ahutchings:feature/portal-support

Jan 6, 2018

+14-8

Commits on Dec 22, 2017

Update AutoSizer to support using a remote window as portal render target
ahutchings
committed
Update HTMLElement instance check to work across contexts
ahutchings
committed