Should relative hosts support be removed from optimizer? #697
Description
Based on ampproject/amphtml#27546 , it sounds like absolute, HTTPS URLs should be required for parameter ampUrlPrefix used in DomTransformer.transformHtml().
In optimizer,
- should we remove support for relative hosts?
- should we require HTTPS URLs?
We should keep in mind that some users may want to test optimized AMP pages in local dev environments (e.g. localhost or HTTP), so it may be best to make no changes.