As of SPR-11792, WebContentGenerator and WebContentInterceptor offer
new APIs and new behavior regarding HTTP caching, including the use of a
new CacheControl class.

Those changes broke part of the behavior in WebContentInterceptor. This
class allows to override the global Cache configuration at the Generator
level, using specific mappings. Prior to this change, those mappings
would not properly apply the HTTP caching configuration when using
deprecated configuration settings in WebContentGenerator.

This change fixes those backwards compatibility issues for
WebContentInterceptor users.

Issue: SPR-13207

This commit adds additional tests to RequestContextHolderTests that
verify proper support for the MockHttpServletRequest managed by Spring
MVC Test in the following scenarios:

- request-scoped service invoked by controller
- session-scoped service invoked by controller
- custom filter that sets request attributes

Issue: SPR-13211

Issue: SPR-12579

Issue: SPR-13210

This commit refactors RequestContextHolderTests in preparation for the
work to be done in SPR-13211.

Issue: SPR-13211

A note is added to suggest the use of @Primary with a
LocalValidatorFactory bean next to the MVC Java config.

Issue: SPR-12194

Conversion and validation documentation related to Spring MVC is now
consolidated in the Spring MVC chapter with references to and from
the Validation and Data Binding chapter.

Examples have been updated to include MVC Java config as well.

Issue: SPR-7301

Also includes an explicit note on stop vs destroy callbacks for Lifecycle beans.

Issue: SPR-13118
Issue: SPR-12882
Issue: SPR-12345
Issue: SPR-11671

Issue: SPR-12896

Issue: SPR-13040

Issue: SPR-13196

Issue: SPR-13205

Issue: SPR-13193

When using Appache Commons FileUpload, multi parts with binary data
(i.e. that are not actual files) are saved and then accessed as
String request parameters.

Before this change however the RequestPartServletServerHttpRequest
used a fixed encoding (UTF-8) while the parsing code in
CommonsFileUploadSupport/Resolver used the encoding from the
content-type header, or the request, or the FileUpload component.

This change does a best effort to determine the encoding of the
request parameter using a similar algorithm as the parsing side
that should work the same unless the encoding comes from the
FileUpload component which is not accessible.

Issue: SPR-13096

Add section on Spring MVC TEst vs full integation testing and provide
reference to Spring Boot's @WebIntegrationTest as an alternative.

Issue: SPR-13169

DefaultSubscriptionRegistry uses deep LinkedMultiValueMap copies between accessCache and updateCache

Issue: SPR-13185

Issue: SPR-13201

Issue: SPR-13185

After SPR-12884 (4.2 RC1) introduced support for a selector header
expression on SUBSCRIBE frames, messages from the destination cache
are further filtered based on the selector expression. While adding a
test to find subscriptions at the same time as unsubscribing, a
potential NPE was exposed. This commit fixes the NPE.

Issue: SPR-13204

Issue: SPR-13200

Issue: SPR-11861

Issue: SPR-13177

Issue: SPR-13194

This commit introduces a test that verifies the fix introduced in
6842fd7f.

Issue: SPR-13079

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

Issue: SPR-13171