MWPW-190597: Enabling locale switch for grouped variations

[mirafedas]

Enables locale switch in the top nav when editing a grouped variation.
In the locale switch dropdown adds "Not translated" label for all locales for which the language copy of this variation does not exist. When navigating to such a locale, the user gets a choice to either view the en_US copy of this variation or create a translation project (works analogously to the default fragment edition).

As for Nala tests, there is an issue with translating in Nala surface - translation project I created fails: https://mwpw-190597--mas--adobecom.aem.live/studio.html#page=translation-editor&path=nala&translationProjectId=769913f5-bde5-4964-a692-8818df465dd0 (I tried two times). To not block this PR I propose to merge it as is and add Nala tests when the Nala issue is resolved.

Resolves https://jira.corp.adobe.com/browse/MWPW-190597
QA Checklist: https://wiki.corp.adobe.com/display/adobedotcom/M@S+Engineering+QA+Use+Cases

Please do the steps below before submitting your PR for a code review or QA

• C1. Cover code with Unit Tests
• C2. Add a Nala test (double check with #fishbags if nala test is needed)
• C3. Verify all Checks are green (unit tests, nala tests)
• C4. PR description contains working Test Page link where the feature can be tested
• C5: you are ready to do a demo from Test Page in PR (bonus: write a working demo script that you'll use on Thursday, you can eventually put in your PR)
• C.6 read your Jira one more time to validate that you've addressed all AC's and nothing is missing

Test URLs:

Before: https://main--mas--adobecom.aem.live/studio.html#expires_in=86399998&fragmentId=3ceec2f2-a508-42a0-bfe6-14f080b9c94e&locale=pl_PL&page=fragment-editor&path=sandbox&token_type=bearer

After:

• Merch card grouped variation translated to pl_PL:
  https://mwpw-190597--mas--adobecom.aem.live/studio.html#expires_in=86399998&fragmentId=3ceec2f2-a508-42a0-bfe6-14f080b9c94e&locale=pl_PL&page=fragment-editor&path=sandbox&token_type=bearer

• Merch card collection grouped variation translated to pl_PL:
  https://mwpw-190597--mas--adobecom.aem.live/studio.html#expires_in=86399998&fragmentId=23bee26c-85fb-402e-aa81-70f841744a99&page=fragment-editor&path=sandbox&tags=mas%3Astudio%2Fcontent-type%2Fmerch-card-collection&token_type=bearer

[aem-code-sync]

Hello, I'm the AEM Code Sync Bot and I will run some actions to deploy your branch.
In case there are problems, just click the checkbox below to rerun the respective action.

• Re-sync branch

Commits

• e51df8e ✅ (latest)
• a4ee1b4 ✅
• 146095a ✅
• 6cdd754 ✅
• ab6d967 ✅

[codecov]

Codecov Report

❌ Patch coverage is 88.61789% with 14 lines in your changes missing coverage. Please review.
✅ Project coverage is 87.44%. Comparing base (5d49c47) to head (e51df8e).

Files with missing lines	Patch %	Lines
studio/src/mas-fragment-editor.js	81.25%	12 Missing ⚠️
studio/src/mas-top-nav.js	84.61%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #806      +/-   ##
==========================================
- Coverage   87.45%   87.44%   -0.02%     
==========================================
  Files         214      214              
  Lines       63827    63871      +44     
==========================================
+ Hits        55821    55851      +30     
- Misses       8006     8020      +14     

Files with missing lines	Coverage Δ
studio/src/reactivity/editor-context-store.js	75.77% <100.00%> (+0.51%)	⬆️
studio/src/router.js	86.69% <100.00%> (+0.11%)	⬆️
...o/src/translation/mas-collapsible-table-row.css.js	100.00% <100.00%> (ø)
...udio/src/translation/mas-select-items-table.css.js	100.00% <100.00%> (ø)
studio/src/translation/mas-translation-editor.js	95.65% <100.00%> (+0.04%)	⬆️
studio/src/translation/mas-translation.css.js	100.00% <100.00%> (ø)
...o/src/translation/translation-common-styles.css.js	100.00% <100.00%> (ø)
studio/src/mas-top-nav.js	99.03% <84.61%> (-0.48%)	⬇️
studio/src/mas-fragment-editor.js	88.89% <81.25%> (-0.60%)	⬇️

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 5d49c47...e51df8e. Read the comment docs.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.