Clean up renderer height styling behaviour

[rtibbles]

Summary

• Removes use of Learn specific height remediations from HTML5 app renderer and PDF renderer
• Reworks styling of PDF renderer to no longer require a global attribute setting on the page html tag, which was causing an issue when the PDF renderer was embedded in pages that needed to scroll independently of the PDF
• Makes styling of the PDF renderer consistent as long as the embedded use of the KContentRenderer has a specified height

References

Fixes #11311

Reviewer guidance

Create a lesson
Manage resources
Try to add a PDF and preview it
Observe that the page can still scroll

View a PDF in Learn, ensure that it behaves as expected

View an HTML5 app in Learn ensure that it behaves as expected

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Testing checklist

• Contributor has fully tested the PR manually
• If there are any front-end changes, before/after screenshots are included
• Critical user journeys are covered by Gherkin stories
• Critical and brittle code paths are covered by unit tests

PR process

• PR has the correct target branch and milestone
• PR has 'needs review' or 'work-in-progress' label
• If PR is ready for review, a reviewer has been added. (Don't use 'Assignees')
• If this is an important user-facing change, PR or related issue has a 'changelog' label
• If this includes an internal dependency change, a link to the diff is provided

Reviewer checklist

• Automated test coverage is satisfactory
• PR is fully functional
• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
• Contributor is in AUTHORS.md

[github-actions]

Build Artifacts

Asset type	Download link
PEX file	kolibri-0.16.0b6.dev0_git.112.gbd937eb4.pex
Windows Installer (EXE)	kolibri-0.16.0b6.dev0+git.112.gbd937eb4-unsigned.exe
Debian Package	kolibri_0.16.0b6.dev0+git.112.gbd937eb4-0ubuntu1_all.deb
Mac Installer (DMG)	kolibri-0.16.0b6.dev0+git.112.gbd937eb4-0.3.0.dmg
Android Package (APK)	kolibri-0.16.0b6.dev0+git.112.gbd937eb4-0.1.0-debug.apk
TAR file	kolibri-0.16.0b6.dev0+git.112.gbd937eb4.tar.gz
WHL file	kolibri-0.16.0b6.dev0+git.112.gbd937eb4-py2.py3-none-any.whl

[nucleogenesis]

Looking through the code things look good. I'll spin it tomorrow so I can better visualize the styles in devtools and test things out.

[pcenov]

Both pdf and HTML resources are displayed correctly except in mobile view where the PDFs are initially displayed in all black that is until the user selects the bookmarks menu. Seems that this is happening when viewing in resolution less than 840 px.

2023-10-11_15-19-14.mp4

[rtibbles]

Interesting, thanks for the check, @pcenov! I'll see what's happening there.

[rtibbles]

OK, I think this should all be working as expected now!

[pcenov]

I confirm - everything is working as expected now.