Date picker shows incorrect date and weekday for Swedish locale

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.1.X, 7.2.X, 7.3.X, Master
• Fix Version/s: 7.1.X, 7.2.10 DXP FP18, 7.2.X, 7.3.X, 7.4.3.9 CE GA9, 7.4.3.10 CE GA10, 7.4.3.11 CE GA11, Master
• Component/s: Tag Libraries > Liferay AUI Taglibs
• Labels:
  • ee-ts
  • liferay-fixpack-dxp-18-7210
  • liferay-fixpack-dxp-27-7110
  • liferay-fixpack-dxp-4-7310
  • liferay-update-dxp-4-7310
  • liferay-update-dxp-6-7413
• Branch Version/s:
  7.3.x, 7.2.x, 7.1.x
• Backported to Branch:
  Committed
• Fix Priority: 3
• Sprint: S05E01 - Dark Souls
• Git Pull Request: https://github.com/liferay-frontend/liferay-portal/pull/1850

Environment

• Version: DXP 7.1
• Fix Pack: dxp-14-7110
• Hotfix: hotfix-5851-7110

Reproduced on: 7.1.x

6927755770e7add43c48772981ae6f2c21491912

The behavior appeared when using French / Spanish keys.
Reproduced on: master

4ceac20a949a25b57642f3a9179f556524154eb0

Reproduction Steps

1. Setup Liferay DXP 7.1 with Fix Pack 14 with hotfix 5851
2. Start creating a new form
3. Add a Date element on it→Publish
4. Add a widget page
5. Add a language selector
6. Add the new form on it
7. Click on the element to show the date popup
8. Assert that the first weekday is Sun
9. Change the language to Swedish
10. Click on the element to show the date popup again
11. Check the day

Expected Behavior
The first day is Monday.

Actual Behavior
The first day remained Sunday.

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