Code in lists could throw error on parse due to inner <code> tag being
parsed but not actually used within a <pre>, so this updates the
importDOM to disregard childdren for code blocks.
This also improves the invariant implementation to not be so
dev/debugger based, and to include vars in the output.
Only actuall added YT in the end.
Google had changed URL scheme, and Vimeo seems to just be something else
now, can't really browse video pages like before.
Also:
- Added svg loading support (dummy stub) for jest.
- Updated headless test case due to node changes.
- Split out editor change detected to where appropriate.
- Added functions to help with testing, like mocking our context.
To provide more control of the summary as part of details.
To support, added a way to ignore elements during import DOM, allowing
up to read summaries when parsing details without duplicate nodes
involved.
Imported at 0.17.1, Modified to work in-app.
Added & configured test dependancies.
Tests need to be altered to avoid using non-included deps including
react dependancies.
