Fix single selection on the same row, item updates

[ahie]

Fixes #2874
Fixes #2872

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This change is 

[gilberto-torrezan]

Reviewed 2 of 2 files at r1.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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flow-components-parent/demo-flow-components/src/test/java/com/vaadin/flow/demo/views/GridViewIT.java, line 112 at r1 (raw file):

                messageDiv.getText());

        Assert.assertFalse(isElementPresent(By.className("v-system-error")));

Is this reliable?
(I asked about this on Slack)
If at some point the box message changes the class name, this test will be green even when a message is shown.
But I don't know a better way of doing this (hence the question on Slack)

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Comments from Reviewable

[gilberto-torrezan]

Review status: all files reviewed at latest revision, 1 unresolved discussion.

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flow-components-parent/demo-flow-components/src/test/java/com/vaadin/flow/demo/views/GridViewIT.java, line 112 at r1 (raw file):

Previously, gilberto-torrezan (Gilberto Torrezan) wrote…

Is this reliable?
(I asked about this on Slack)
If at some point the box message changes the class name, this test will be green even when a message is shown.
But I don't know a better way of doing this (hence the question on Slack)

Kirill answered with a code that inspects the error messages in the client console. That is more reliable, and could be exported as an Util method for other tests that need the same functionality.

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Comments from Reviewable

[ahie]

Review status: 1 of 3 files reviewed at latest revision, 1 unresolved discussion, some commit checks failed.

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flow-components-parent/demo-flow-components/src/test/java/com/vaadin/flow/demo/views/GridViewIT.java, line 112 at r1 (raw file):

Previously, gilberto-torrezan (Gilberto Torrezan) wrote…

Kirill answered with a code that inspects the error messages in the client console. That is more reliable, and could be exported as an Util method for other tests that need the same functionality.

Done.

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Comments from Reviewable

[gilberto-torrezan]

Reviewed 2 of 2 files at r2.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable

[gilberto-torrezan]

Review status: all files reviewed at latest revision, 1 unresolved discussion, some commit checks failed.

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flow-components-parent/demo-flow-components/src/test/java/com/vaadin/flow/demo/views/GridViewIT.java, line 112 at r2 (raw file):

                messageDiv.getText());

        Assert.assertFalse(getLogErrors().findAny().isPresent());

The problem in CI might be that the code also gets all warnings, and you just want errors.

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Comments from Reviewable

[gilberto-torrezan]

Reviewed 2 of 2 files at r3.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable