Non-fieldable entities (with only base fields) cannot be configured translatable, eg. shortcuts

Uploading an easier to review patch which shows the removed condition commented out (and does not have indentation changes for the removed wrapping condition). And an actual patch for testing that does (but looks like a lot more changes which is just for the indentation).

@YesCT: right, that is the gist of the patch, we try and collect and translatable fields including base fields, and only add the entity bundle level checkbox, if we found any -- instead of inferring that from configurable fieldability which should not be a requirement.

In fact, instead of adding that workaround, I'm postponing this on #2310475: Admin theme for translation tabs just works for nodes, which now has complete tests and almost committed.

Now rerolled without the workaround now that #2310475: Admin theme for translation tabs just works for nodes landed.

Rerolled since it did not apply due to a dead code line removed.

Now with a test! Not yet fully passing but resolved a few hair-pulling things:

- ContentTranslationTestBase.php adds a custom field on the entity which obviously cannot be done if its not fieldable, we need to make that conditional, done.
- MenuLinkContentUITest was setting a custom field name, which was useless; it is fieldable so no need to
- Shortcut sets are bundles for shortcuts but this was not defined in the annotation, (automated permissions for translations did not work, so test users could not be created, fun to debug :)

Local fails are now down to the default language titles not properly setting.

So the remaining fails are only due to us using the title base field in the test, so we should not try to force the default value either, since the test wants to control it. As soon as we let the test fill in the title value (since we tell it to use it in $this->fieldName), it is fine. So that's it :) Reviews please.

Yeah the shortcuts did not show up translated and I thought to fix it in another issue, but we can just as well prove it here and integrate it into the test. Works :)

On the links in the translation overview, they are borked for ALL entity types, same problem applies to node articles. I'll submit another issue shortly, I think I have a patch.

Patch was beautifully green locally (multiple times). Making the xpath test more robust, so it should not fail on escaped stuff or whitespace getting in the way.

So the full href may be different if the site is in a directory of course. Use a contains() like other tests do.

All right I'm down to having no idea why this breaks. All prior versions of the patch have been green locally. Duh. Will need a patch testing issue splintered with debug messages :(

Decided to use this issue to figure this out. It should not be that far away #famouslastwords

Duh, looks like all paths requested display the untranslated shortcut / not language dependent path.

Looks like path access checking got stricter in the meantime, now we cannot set a shortcut to the admin page, so translations did not save. We should use a less restricted path in the test, the user path is good one.

Needed a reroll due to #2224761: Add a generic way to add third party configuration on configuration entities and implement for field configuration.

This new rerolled patch passes on the simpletest UI locally (139 passes, 0 fails, 0 exceptions, 52 debug messages) but fails miserably on run-tests.sh (49 passes 51 fails 34 exceptions 29 messages). Uhm, now what? Neither reproduces the situation happening on testbot.

All right, because it is a page not found, the language will not be recognised either. Duh. Fixing this up then. Thanks @berdir.

Now uses $language natively on drupalGet(), thanks @berdir for the tip. Still has some debugging code in it which should be removed once/if passes finally. (Passes locally).

All right, removing debug code. I think this should be ready to go in now :) @plach what do you think?

Amazing, so glad this works now :) Not for shortcuts per say, but for the coherence of the system in general.