Data storage overlap

[xylix]

When reviewing apinf/platform#2787 platform devs @matleppa and @marla-singer found an issue when trying to use multiple instances of OpenAPI designer under the same domain. They shared their data, even though user expected every "instance" of OpenAPI designer to have their own form data.

[tulir]

Changing this from within OpenAPI designer would be quite difficult. OpenAPI designer currently has no idea about the state of the wrapper, so those different instances are actually all the same (since it's the same domain). It's much easier to have the wrapper tell designer what data to display (related: #327)