Issue: SPR-13761
(cherry picked from commit 3d1ae9c6)

Issue: SPR-13760
(cherry picked from commit cd4ce872)

Issue: SPR-13745

Issue: SPR-13753
(cherry picked from commit 747863d5)

Issue: SPR-13548

Issue: SPR-13566

Issue: SPR-13545
(cherry picked from commit 966f95b9)

XhrTransport implementations do not need to redeclare interface when extending from AbstractXhrTransport
(cherry picked from commit df0b26f0)

Issue: SPR-13326

Before this change <websocket:decorator-factory> decorated to
the SubProtocolWebSocketHandler RootBeanDefinition rather than
using a RuntimeBeanReference, which led to a separate instance
of SubProtocolWebSocketHandler to be created.

Issue: SPR-13190

(cherry picked from commit 92bf32b9)

(cherry picked from commit e0a11f2a)

Issue: SPR-13019
(cherry picked from commit 02d28ae9)

Issue: SPR-12956

Prior to this commit, the `client-library-url` XML attribute was not
effective in the MVC namespace, leaving the default value configured:

```xml
<websocket:sockjs client-library-url="/js/sockjs.js" />
```

This commit fixes the sockjs namespace handler and makes sure that this
attribute is configured on the `SockJsService` Bean to be created.

Issue: SPR-12874

(cherry picked from commit d23893fd)

(cherry picked from commit 2b340946)

Issue: SPR-12728

Issue: SPR-12727

This commit adds support for a same origin check that compares
Origin header to Host header. It also changes the default setting
from all origins allowed to only same origin allowed.

Issues: SPR-12697, SPR-12685
(cherry picked from commit 6062e155)

This commit introduces the following changes:
 - Requests without Origin header are not rejected anymore
 - Disable Iframe when allowedOrigins is not empty and not equals to *
 - The Iframe is not cached anymore in order to have a reliable origin check
 - allowedOrigins must not be null or empty
 - allowedOrigins format is now validated (should be * or start by http(s)://)

Issue: SPR-12660
(cherry picked from commit 9b3319b3)

Before this change the WebSocketTransportHandler passed
Collections.emptyMap as attributes to the HandshakeHandler because
it didn't matter what attributes the underlying WebSocketSession has
since it is wrapped by the SockJsSession and that's what exposed for
use everywhere.

This change has the WebSocketTransportHandler passing the attributes
from the SockJsSession instead since it's more accurate for the
underlying WebSocketSession to have access to the same map instance
and it allows the HandshakeHandler to change the attributes even if
it doesn't need to do that today.

Issue: SPR-12716

Issue: SPR-12658

The following two refinements have been added:
1) SockJS doesn't support binary messages so don't even try
2) don't bother if payload.length == 0

Issue: SPR-12475

After this change the StompSubProtocolHandler sends STOMP frames
with content-type=octet-stream as a binary WebSocket message.

Issue: SPR-12475

Issue: SPR-12516

This commit introduces the SpringHandlerInstantiator
class, a Jackson HandlerInstantiator that allows to autowire
Jackson handlers (JsonSerializer, JsonDeserializer, KeyDeserializer,
TypeResolverBuilder and TypeIdResolver) if needed.

SpringHandlerInstantiator is automatically used with
@EnableWebMvc and <mvc:annotation-driven />.

Issue: SPR-10768

With this commit, Jackson builder is now used in spring-websocket
to create the ObjectMapper instance.

It is not possible to use the builder for spring-messaging
and spring-jms since these modules don't have a dependency on
spring-web, thus they now just customize the same features:
 - MapperFeature#DEFAULT_VIEW_INCLUSION is disabled
 - DeserializationFeature#FAIL_ON_UNKNOWN_PROPERTIES is disabled

Issue: SPR-12293

Issue: SPR-12497

(cherry picked from commit 7e07f3d0)

Upgrade undertow dependency to 1.1.0.Final.
Add support for undertow 1.1.0.Final in the
UndertowRequestUpgradeStrategy, after a breaking change in the
`io.undertow.websockets.jsr.ConfiguredServerEndpoint` constructor.

Issue: SPR-12302