Fixes #8840

* Use computed style for Escalator size calculations

The old method of using getBoundingClientRect does not work as expected
if a transform has been applied to the element or one of its parents.
For instance PopupView animates itself using a scale(0) -> scale(1)
animation. When scale(0) is active, getBoundingClientRect will return 0
for all sizes while computed style ignores the transform and returns the
expected value.

Fixes #8793

* Use textContent instead of innerText in TextRenderer

This improves standards compliance and reduces unnecessary layouting.

Optimization suggested by Oskar Hýbl, Cleverbee solutions

Fixes #8790

* Add dropEffect parameter to DragEndEvent (#8895)

* Remove drop effect from drop event (#8895)

* Make sure that drop effect is not null

Fixes #8590

This patch also enables an old test that was pending #8128

Fixes vaadin/framework8-issues#556

Fixes #8846

* Remove API for setting arbitrary drag data
* Store the drag source component in the UI

Fixes #8893

Allows Flash embed to expand if percentage dimensions given

Fixes #4035

* Optimize grid by avoiding redundant row refreshes

* Delay more calls to refreshBody()

Closes #8795

* Add missing since tags for 8.1.0.alpha1

* Update @since for DataCommunicatorClientRpc

* Update @since for DataCommunicator

Fixes #8416

* Rename getMaxEscalatorRowCapacity to describe what it does

* Always calculate Escalator max row count the same way

This changes Escalator to not take a horizontal scrollbar
into account when trying to determine "maximum visible rows". This will
add another row, compared to previous versions, when there is a horizontal
scrollbar. In reality, it would likely make sense to always add 10 more rows
to have some buffer above and below the visible area.

Fixes #8661

Do not calculate column widths unnecessarily, especially for columns
with fixed width.

Fixes #8678

* Initial HierarchicalDataProvider for TreeGrid
* Initial in-memory hierarchical data implementation
* TreeGrid declarative support

Fixes #8611, Fixes #8620

Closes #8250

* Fix removing rows from the middle of Escalator

Fixes #8825

* Fix detach of grid when it contains frozen columns

Fixes #8748

Fixes #8778

Fixes #8622 
Fixes #8623

Columns unregister themselves from the grid through removeColumn, also
when the whole grid is removed.

Fixes #8748

Fixes #8728

Synchronises parts of compatibility package code to match 7.7
Picks suitable patches for 8 code as well

endDependencyLoading that was used for starting to load the deferred
connector bundle is only called during regular application init if the
theme wasn't yet loaded when the initial UIDL request finished.

With this patch, the bundle is instead set to be loaded after the
initial UIDL message has been completely processed.

Fixes #4763

* Fix exception when no columns are shown or all columns are frozen

Fixes #8329

* Fix partial state change handling of JavaScript components

In ace0e324b6 (Use diffstate for JS connectors) 
partial state change handling for JavaScript components was introduced, but the
setNativeState method in JavaScriptConnectorHelper was not adjusted.
By removing the cleanup code from the updateNativeState method it can 
be ensured that the non-changed properties are still present on the state object.

* Add test for preserving untouched JS state fields

* Add @author and @since tags to drag and drop related new files (#8693)

* Add initial implementation of TreeGrid

* Refactor TreeGrid and related classes

* Fix potential class cast exception in TreeGrid#getDataProvider

* Add smoke tests for TreeGrid

* Add communication constants for TreeGrid

Use shared constant values for hierarchy data serialization and deserialization

* Fix event ordering in TreeGrid, add javadocs, keyboard navigation test

* TreeGrid improvements

* Add TreeGrid.getDataProvider to StateGetDoesNotMarkDirtyTest exclude list

* Merge remote-tracking branch 'github/master' into tree-grid

* Remove getEscalator override from TreeGrid

* Make DragSource extension/component available in DropEvent (resolves #8439)

* Update drag and drop test to use new API

* Change type of drag source and update javadoc

* Use existing data map instead of DataTransfer

A login page you want to redirect to is typically in the webapp root,
which you can now refer to as "Vaadin-Refresh: context://login.html"

* Fix java packaging order (#106)

Closes vaadin/archetypes#113

* Use proper UTF-8 encoding for Content-Disposition filenames (#19527) (#6607)

* Enable changing the backing bean for BeanItem (#4302) (#77)

When storing a bean to the database, you typically get a new and updated
bean instance back. By allowing to change the bean instance, we make it
possible to just update the single BeanItem instance which can be used
in many places.

* Make AtmospherePushConnection methods public (#7973)

There is no sensible way to use a custom version of APC, so protected
access does not help in any way to access the underlying resource and/or
connected UI.

* Use correct indexes in multiselect checkboxes after removing rows (#8072)

Fixes #8011

* Fix removal of hidden Grid columns (#8071)

Fixes #8018

* Call error handler for exceptions in UI.init() (#8055)

Fixes #4995

* Render font icon correctly on the 'more' menu item (#8126)

* Render font icon correctly on the 'more' menu item

Fixes #8125

* Reopen Grid details on attach, fixes #8015 (#8074)

Fixes #8015

* Fix broken Grid tests after picking changes from 7.7.7

Removed duplicate setDetailsVisible calls from onDetach

* Correctly detach components in merged cells when a static row is removed (#8142)

Fixes #8140

Fixes #2523

* Replace usage of getParent() to prevent client side NPE during onUnregister() (#8646)

Fix since tags for the server and shared modules and new types in client.

* Reduce ComboBox initial requests

Use initial fetched data on client side,
do not request data from server side for each time popup is opened.
Fixed initial filter being null for ComboBox on DataProvider,
causing unnecessary size & fetch for not-changed filter.
Fixed ComboBox sending default filter unnecessarily to server.
Fixed wrong page indexing in VComboBox -> ComboBoxConnector.

Fixes #8496
Fixes vaadin/framework8-issues#488

* Fix last item missing

When pageLength was 0 and nullSelectionAllowed,
the last item was not shown. Tried to sensify the API
for total suggestions versus total suggestions + null selection item.

* Fix ComboBox selected item updates

Handles changing of ItemCaptionGenerator or ItemIconGenerator,
need to update the selected item caption and icon separately.
Previously it worked because all data was sent all the time to client.
Doesn't fix the issue, when selected item is updated with refreshItem(),
and it is not on the active range that will be sent to client.
For that, ComboBox would need a separate notification about item update.

* Updated screenshots

* Add DragSource Extension (#8169)

* Add DropTarget Extension (#8170)

* Add DragStart Event to DragSource Extension (#8171)

* Make DataTransfer.dropEffect configurable (#8174)

* Make DragSource.dataTransfer data configurable (#8172)

* Add server-side Event for drop (#8177)

* Added license headers

* Extract handler methods, move DropEvent and DropListener to new file, move enums to top

* Replaced LinkedHashMap with Map and added List to preserve order of data

* Add API for adding a JS acceptance criteria for dragover and drop (#8178, #8179)

* Make DragSource Extension extendable (#8175)

* Make DropTarget Extension extendable (#8176)

* Added javadoc to protected methods

* Moved EffectAllowed to shared so that it could be used in shared state directly

* Moved DropEffect to separate file, some review fixes and javadoc

* Added list to DropTargetRpc to preserve order of data

* Remove event listeners on unregister

* Changed method names set/getData() to more descriptive set/getTransferData()

* Add server side dragStart event (#8171)

* Add style to prevent text selection to allow drag

* Remove target indicator style on drop

* Add client side dragend event listener for drag source

* Add server side dragend listener.
Attach client side listener only when server side listener added.

* Add drag source information to server side dragstart and dragend events.

* Fixed some issues addressed in review

* Trigger server side dragstart only when there is a listener attached

* Criteria script can be set as null to clear

* Use Js Interop instead of JSNI for handling event listeners

* Use elemental package instead of Js Interop for handling event listeners

* Add missing javadoc for public methods

* Add default value "uninitialized" to effectAllowed parameter

* Simple test UI for HTML5 DnD functionality (#8395)

* Add javadoc and other minor changes

Don't implement handlers on widget level.

Fixes #8422

Fixes vaadin/framework8-issues#463

Fixes  #8405

* Fix problem with re-opening the popup (#8446)

Fixed problem that disables opening of popup
after closing it by clicking the datefield-button.

* Fix issue #8446 in compatibility version PopupDateField also.

Schedule column ordering so that possible onUnregister methods get run first.