- Don't stamp the template repeatedly when attaching.
- Don't use __proto__
- Store the template in an external map instead of a property on the prototype.
- Add a created() callback.
- Allow creating a SkyElement with no associated <template> or ShadowRoot.
R=rafaelw@chromium.org
Review URL: https://codereview.chromium.org/715203002
Expose a Document constructor instead. This also exposes that
the TemplateBinding library might need more control over the
registration context for custom elements. For now we make all
documents share the same registration context.
R=ojan@chromium.org, abarth@chromium.org
Review URL: https://codereview.chromium.org/697363002
