* Check whether className is of type string

* Move string type checker method to widget util

* Fix formatting of WidgetUtil

* Break svg into lines

* add role="row" and role="gridcell"

* optimize code and add additional rows for the header

* add simple test

* improve code and add rowgroup

* add debug log

* add more log to test

* remove debug test info and add role before appending to tr

* wording - change contains to contain

* create enum for magic strings, change comments and method signature

* rename enum to be singular and rename param roleName to role

* update javadoc, rename and make enum public

* Use .toLowerCase and .toUpperCase(Locale.ROOT)

* Spaces

* add spaces after if(

* Add spaces after 'if' and 'for' in JavaScript

* Revert to old format

* Remove whitespaces

* Simplify lambda expressions

And remove unneeded 'return' keyword.

* Format

Fixes #9763
Fixes #9978

Fixes #9200

Fixes #9792

This is based on discussion from vaadin/vaadin-grid#1023 .

Opening grid editor from server side.
Fixes #8477.
Addressing #8820 will be the user's responsibility as fetching index of item might be slow.

Also adds aria-selected for grid rows.

Also removes dependency on junit.framework.TestCase .

And remove unused imports.

Converts Notification to an Extension and adds support for listening to the closing of notifications.

Fixes #888

* Navigator now by default uses pushState and normal URLs

* added documentation for pushState and updated Navigator documentation

* improving docs etc, adding one TODO to be solved before merging

* pushState/replaceState no work better with changing titles

* Making uri fragment navigator work when not using specially mapped UI

* Revert to older default, add annotation for selecting

* Fix tests, add null checks

* Reorder if-clause, fix tests

* Revert unnecessary test change

* Use correct variable in UI, fix test clean up

* Updates to JavaDocs, fix some methods and tests

* Add comments, fix test ui, TODO for fallbacks

* Navigation documentation, JavaDocs, removed TODOs

* Documentation fixes

* Improve JavaDocs

* Fix link name in documentation

* Improve throws declaration in getLocation

* Change documentation about the PushState based navigation

* Add since tags

* Add since tags for UI

Add additional class names and style to components and error indicators to distinguish different error levels.

Vaadin 8 implementation of #9816. Cherry picked changes and added compatibility package component changes and tests.

Resolves #3139

If a GridLayout is used and font loading is not complete, force another layout after all fonts are loaded.

Fixes #9921
Fixes #8207

Fixes #9868

And use varargs in a test.

And some trivial test enhancements

And remove unused imports.

After this change, .gitattributes will take care of keeping native
line endings.

* Replace CRLF with LF in non-Java files

Also includes some other minor cleanup.

Fixes #9018

Component error was cleared after selecting a date from
calendar popup, even if the date is invalid due to
validation errors or if user programmatically sets an UserError.

This change inverts the order of setValue() and setComponentError(null) in order
to preserve errors set by ValueChangeListeners (e.g. Binder validators).

Fixes #10011

This adds basic support for aria-sort for Grid (https://www.w3.org/TR/wai-aria-1.1/#aria-sort).

- aria-sort is not added, if the column is not sortable
- aria-sort="none" is added, if the column is sortable but currently not sorted
- aria-sort="ascending" is added, if the column is sorted by asc
- aria-sort="descending" is added, if the column is sorted by desc
- aria-sort="other" is added, if more than 1 column is sorted, currently there is no aria-sort-order

Under certain circumstances IE 11 (11.0.45 / 11.0.9600.18762) produces an exception when collapsing/expanding rows (particularly the first child after the very first element) in a TreeGrid within a Window.

This workaround removes the row explicitly before inserting, instead of letting JS handle it.

Fixes #9850

Fix connector tracker cleanup for the case where a component is
hidden by a request and is made visible again by push.

This fixes a regression caused by #9305.

Fixes #9905

The related tests have a workaround for another (Chrome specific) GridLayout bug #9921.
Those workarounds should be removed once that issue is fixed.

Fixes #9148

Position caption correctly when using different vertical alignment than TOP in GridLayout.

Fixes #7895

Try to make the test more stable by using a different way of
detecting the presence of a notification. This approach is used e.g.
in GridComponentsTest.

Correctly render components that handle their own captions inside
a Composite.

Fixes #9848

Keep the ComboBox popup at the same position relative to the ComboBox
when the view is scrolled.

Fixes #5043

When child components are removed from a
VerticalLayout/HorizontalLayout, do not remove other children from the
DOM if no other hierarchy changes are made.

Fixes #7713