Binder.validate() no longer fails with "bean level validators have been configured but no bean is currently set" when in buffered mode

[mvysny]

Description

This PR makes the Binder.validate() implementation in line with its javadoc. Namely, Binder.validate() no longer fails with "bean level validators have been configured but no bean is currently set" when in buffered mode, which is according to the current javadoc: "Bean level validators are ignored if there is no bound bean or if any field level validator fails."

Fixes #18120

Type of change

• Bugfix
• Feature

Checklist

• I have read the contribution guide: https://vaadin.com/docs/latest/guide/contributing/overview/
• I have added a description following the guideline.
• The issue is created in the corresponding repository and I have referenced it.
• I have added tests to ensure my change is effective and works as intended.
• New and existing tests are passing locally with my change.
• I have performed self-review and corrected misspellings.

Additional for Feature type of change

• Enhancement / new feature was discussed in a corresponding GitHub issue and Acceptance Criteria were created.

[github-actions]

Test Results

1 092 files  ± 0  1 092 suites  ±0   1h 21m 52s ⏱️ -42s
6 821 tests ± 0  6 775 ✅ ± 0  46 💤 ±0  0 ❌ ±0 
7 133 runs   - 37  7 075 ✅  - 37  58 💤 ±0  0 ❌ ±0 

Results for commit 1a5d08d. ± Comparison against base commit dc68b28.

This pull request removes 3 and adds 3 tests. Note that renamed tests count towards both.

com.vaadin.flow.data.binder.BinderTest ‑ beanvalidation_isValid_throws_with_readBean
com.vaadin.flow.data.binder.BinderTest ‑ beanvalidation_validate_throws_with_readBean
com.vaadin.flow.data.binder.BinderTest ‑ isValidTest_unbound_binder_throws_with_bean_level_validation

com.vaadin.flow.data.binder.BinderTest ‑ beanvalidation_isValid_passes_with_readBean
com.vaadin.flow.data.binder.BinderTest ‑ beanvalidation_validate_passes_with_readBean
com.vaadin.flow.data.binder.BinderTest ‑ isValidTest_unbound_binder_passes_with_bean_level_validation

♻️ This comment has been updated with latest results.

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication

[mshabarov]

This should be postponed until major release of Flow (25), as this is a behaviour change.

[sonarcloud]

Quality Gate passed

Kudos, no new issues were introduced!

0 New issues
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud