Add translatability & placeholder message for blocked data-src elements (iframe, ...) [D8 + D7]

I'll start with the development of this feature soon.

Patch attached, please review! This patch is based on #3098778: Add schema (& translatability) #3 so that patch cookiebot_add_schema-3098778-3.patch has to be applied before!

This is what the form looks like:

TODOs:

• Message is added multiple times if the consent banner is closed without consent
• See markup below checkox
• Remove "?" from checkbox label

Thank you @a.milkovsky for your feedback! Yes that's a good idea. I'd suggest to put this into the database, otherwise it would be much less flexible because of the splitting, do you agree?

Please <a href="!cookiebot_renew" class="cookieconsent-optout-marketing__cookiebot-renew">accept marketing-cookies</a> to view this embedded content from <a href="!cookiebot_from_src_url" target="_blank" class="cookieconsent-optout-marketing__from-src-url">!cookiebot_from_src_url</a>

Attached is a new patch which fixed the points from #9 and wraps and explains the form elements a bit better.

I'll add a new patch after your reply containing the template.

Completely new patch attached based on #5 from #3098778: Add schema (& translatability) (can we please get that done do proceed in other issues first?).
I now implemented your suggestions from #10.

Please review.

I decided to add a complete patch now, which includes Patch from #3098778: Add schema (& translatability)-#5 now and will be easier to test.

It also contains a further change of

if (!$config->get('cookiebot_show_declaration') || empty($cbid)) {

from #14 which is required due to the change to boolean. Before the code was strictly compared to !== 1 which fails with a boolean schema.

Hi @arnested,

thank you for your feedback!

#15 will of course be resolved with a final patch. It was created while the other issue was in work. Sorry. Thank you for the hint.

#16:

Is there any reason this only handles the marketing category?

Yes, I also thought a lot about it. Looking into the cookiebot automatic code, the data-src automatism always sets this category. Blocked sources will 99,9% be Marketing, I can't imagine many cases where an iframe or video is "statistics" or "preferences".
We could also add a separate text for each type or remove the type completely / match all, but as of YAGNI I'd only add what is currently needed. It will be simple to add the same for other categories when needed.

Would you like to use that feature for statistics? (look at the JS code) or would you solve it differently anyway?

Well I think that's a huge disadvantage for users and from my perspective content doesn't belong into template. It would require every page owner / admin to know about theming to change the texts and placeholders.
The text and the placeholders are definitely config, I think and I would suggest to leave this as it is as a good compromise. Anyway, it's just my opinition and I think there is no "real truth" :)

Any more feedback? Can we set this RTBC and commit to dev?

Note to myself: Before commit I have to recheck, why these lines were removed and if it was intended or by mistake:

-  else {
-    $cookiebot['#attributes']['async'] = 'async';
-  }

Final patch now with correction from #24 and basic CSS for the placeholder message.
Please review and test. This now includes #3098778: Add schema (& translatability) which is also essential for the message to be translatable. This way it will be easier to ship.

Not my day, I selected the wrong patch, sorry. Now here we go.

Codesniffer fixes.

D8 Codestyle fixes and Drupal 7 backport attached.

D7 version is failing, because it is based on #3100878: Backport important functionality to Drupal 7 which should be committed first. Afterwards we should proceed with the backport here.

I committed #3100878: Backport important functionality to Drupal 7 to 7.x-1.x so we can now proceed with these improvements / backports to 7.x!

Ok the Drupal 7 version is also ready. The remaining 4 codesniffer entries are OK and intended, because it's a reset for inline styles set. Ready for RTBC! :)

Committed to dev in 7.x and 8.x - thank you all!