* Add delay to the unstable test

* Fixes 11517. Use ENTER and SPACE keys as shortcuts for header buttons

* Merge branch 'master' into fix-11517

* Increase sleep time for test failing in validation

* Merge branch 'master' into fix-11517

* Update screenshots after chrome updates

* Update screenshots after chrome updates

* Reset selection on DataProvider change in RadioButtonGroup

Fixes #11454

Other components needing the same fix are ListSelect,NativeSelect,Combobox (The ones implementing HasDataProvider and extending AbstractSingleSelect. Grid is not affected as it extends AbstractListing and hadles selection differently)

* Added test case

Verify that ValueChangeListener is actually fired after value is reset setting new DataProvider

Fixes 11528

Verify that correct mode(HTML/TEXT) of caption is set for the  Panel
Fixes #11521

Add DataChangeHandler removal in v7 Grid just as in v8 Grid.
Adding tests to the fix to verify, that NPE is not thrown.

Add check for the V8 TextField used in Table in compatibility mode. This makes clicking cell with the TextField select the row, preserving behaviour from V7.
Through, as it's noted also before, this is an improved workaround, not a proper solution to address the issue.

Fixes #11474

Make improve of caching for hierarchical data optional

Fixes #11477

Explicitly reset the value in case if it was cleared.
Ignore the case for selecting a suggestion.

Fixes vaadin/testbench#1122

* Add Test file

* Remove redundant check for for Firefox

It seems that in older versions of Firefox (at least, older than 45) the KeyPress event should be used instead of KeyDownHandler. At some point (works already on 58 version, the current one is 65) the issue was resolved and starting from Firefox 65 this hook prevents from navigating in the pop-up via keyboard.
Simply removing additional logic makes navigating in both DateField and InlineDateField possible

Fixes #11465

Checking that no prior Combobox behavior is broken

* Cleaning-up the code

Adding UI test

* Adding TestBench test

* add accessor methods for CUSTOM_SERIALIZERS in JsonCodec

* javadoc

* removed removeCustomSerializer method, renamed putCustomSerializer to addCustomSerializer, added sanity checks and JavaDocs

* refactored addCustomJsonSerializer to set, added test UI

* move enums to be parsed after custom serializers

* move adding custom serializer to static block

* throw an exception if multiple serializers are registered for class

* updated javadocs

* changed CustomJSONSerializerTest to a SingleBrowserTest

* moved CustomJSONSerializerTest to server/ and it's now not a browser test

* removed CustomJSONSerializerTest

* Fix an NPE caused by the previous fix to Grid's frozen columns (#10653)

If the user managed to get two frozen column count changes into a single server round-trip before the component had been attached, the previous fix  #11346 lead to a null pointer exception since there was no diff state available.

This fix adds a null check before removing the frozen column count value from the diff state so that this will not happen.

Closes #10653

Clear contents of iframe clone that is in a Window so that when it's reattached to DOM we don't get 404

* add possibility to configure nested null behavior to Grid.Column

* added addColumn method that allows configuring the nested null handling behavior of the column

* added uitest for nested null value handling, implements #11137

* Some formatting changes

* add client side integration for custom styles for checkbox.label and checkbox.input

* add server side integration for checkbox element styling

* add server side tests

* add client side test

* Improve VMenuBar click handling logic

During `updateFromUIDL` inside MenuBarConnector we empty and re-instantiate the components of MenuBar. When we are modifying the Menubar from the BlurEventListener of another component, we ,by this, remove widgets, therefore clickEvent is not fired and the action of the MenuItem is not proceed as a result. (The BlurEvent is fired before the click event in the chain of events. )

To improve the situation, we catch onMouseDown event , which is fired before BlurEvent,by assigning mouseDown flag to true. Then if no click event has yet happened, we delay the execution of update inside `updateFromUIDL` by default 500 ms. Then if click event occurs, it proceeds normally. The time can be increased/decreased using setter.

There is no delay, if we are clicking on the MenuBar as usual or no Blur listener is set.

This change allows setting descriptions

* Remove accidentally committed comment

* Don't update the state on the getDelayMs call

* Fixes #10814

* Add missing tests

Fixes #11374

Update screenshots due to update of search-minus and search-plus icons values

* Move onClick logic to the Connector

Move onClick event handling from 'VNativeButton' to NativeButtonConnector. Now works as for regular button.

Also, adding propagation of the `enabled` value to the state on disableOnClick being true

Fixes https://github.com/vaadin/framework/issues/11188

Setting read-only state to CheckBoxGroup should disable adding clicking effect. Missing v-readonly style is added to every CheckBox in the component, if it's set to read-only.

Fixes: https://github.com/vaadin/framework/issues/11113

* Add file missed from initial commit

* Verifying that option is enabled

Some of the options might be disabled on there own. Verify that option is not disabled, before removing disabled styles.

* Add missing test file

* Request data update before client response

* fix the accidental commit

* add tests

fixes #11320

* Add missing FocusShortcutListener

Was removed from 8.0 and not readded.

Fixes #8297

* Update Release note for this change

In certain cases setting the frozen columns didn't produce the expected result in the client side widget state. This happened if the frozen columns value was set to be the same it was before removeAllColumns was called.

This fix removes the frozen column value from the diff state so that the value gets properly set in the client side.

Closes #10653

* Add more context information to criteriaScript in GridDropTargetConnector

When using drag and drop in Grids and TreeGrids a criteriaScript can be specified.
However, this criteriaScript only gets an event as input parameter.
It would be helpful if the criteriaScript would get more information:
- the DropLocation
- the targetElement which is used as a base for the DropLocation

This change provides a protected method in DropTargetExtensionConnector
which decides, if the drop is allowed by the criteriaScript.
This method is overriden in GridDropTargetConnector to
provide the both parameters dropLocation and targetElement.

* add Test UI for criteriaScript with targetElement and dropLocation

* add some description for the Test UI

- When rows are added, details row heights need to be taken into account
in positioning.

Fixes #11348

* Fix colorPicker tests

In IE11, the click-layer needs longer time to load.

* Revert "Update ComboBox internal state on new item added (#11094)"

This reverts commit 56ce91c616.

* Add tests to verify the issue

* Fix for setting default row height for a Grid with details row(s) open.

- Details row(s) should be taken into account when the rows are
re-positioned after getting new heights.

Fixes #11325

This refactoring addresses two issues cased by dropping updatedData before it was processed. Issues arise , when visibility has change.

Fixes #11274 and similar issue within RadioButton

There is no reliable way to test automatically NativeSelects in Grid, but adding UI test, at least

Fixes #11276 

Refactor the code and correct the logic for validation

Rename an internal variable, as it contains more than one type of messages

Fix upload issue

* Make value changes in color picker user originated

This is not a programmatically initiated event, so it should have the
'userOriginated' property set to 'true'.

 - Added test to verify that indeed event is user originated after the change

* Add Test for closing window with focused textfield

verify issue #10642

* Refactor the code about using keyMapper

Fix https://github.com/vaadin/framework/issues/11268

```buildTime()``` function re-initializes ListBoxes for hours,minutes and seconds values. We need to set correct values in those ListBoxes, before assigning value to the labels displayed instead of those ListBoxes in ReadOnly state, as , otherwise, the selectedItemIndex returns 0.

* Fixes #10937

- Previously if selected value is null, then index is set to -1; in current implementation if value is null and emptySelection is allowed then set the index to 0. (The position for the empty selection)

- Also, if changing the allowEmptySelection on the fly, ensure, that either index is to-reset to -1 by setting the selected value to null on the client-side (the value before was null) or preserve the value(value was different than empty).

* Change the test case

Since in this pr the behaviour of the NS is changed, therefore old test need to be adjusted.

Change: setting null as value will select empty selection. Before that nothing would be selected and value will be cleared.

Behaviour change in PR: Allow selecting null as value

* Rebuild calendar pop-up on readOnly state change

Fixes https://github.com/vaadin/framework/issues/6565

* Test case for removing Grid with components

* This reverts commit b2745dc14f.

Add test case to address the issue with removing gird with components;
Current situation: the grid cannot be removed and client-side throw an error. 
fixes: Revert the corresponding change, as it didn't address any issue which was fixed.