Image Preview resizing content

On the Polymer 3 and ESM migration we found that a bug (ELEMENTS-1141) with our integration with CropperJS.
That ticket was resolved and some notes where added to explain the issue. Also unit tests were included. 

In the meanwhile we found that we probably missed one scenario: when we collapse the metadata layout.

Steps to reproduce

1. Go to nightly.nuxeo.com and open any image asset 
2. Check the image is displayed with the correct (i.e. expected) size on the previewer;
3. Collapse the metadata layout;
4. Check the image is size is not adapted;