Issue: SPR-17536

ResolvableType-based matching consistently respects generic factory method return type (even for pre-initialized raw singleton instance)

Issue: SPR-17524

(cherry picked from commit ebbe14c3)

Also includes Hibernate ORM 5.1.16 for integration tests.

Also includes Apache HttpClient 4.5.6 and HttpAsyncClient 4.1.4.

Issue: SPR-17439

(cherry picked from commit 77ab88b1)

Prior to this commit, parallel invocations of
MethodParameter.findParameterIndex() (invoked indirectly via
SynthesizingMethodParameter.forParameter() and
MethodParameter.forParameter()) could intermittently lead to an
IllegalArgumentException being thrown due to a race condition in the
internal implementation of the JDK's
java.lang.reflect.Executable.getParameters() method.

This commit addresses this issue by introducing a fallback for-loop
that iterates over the candidate parameters a second time using
equality checks instead of identity checks.

Issue: SPR-17534

(cherry-picked from commit 81fde5ec)

Prior to this commit, parallel execution of @BeforeEach and @AfterEach
methods that accepted @Autowired arguments would fail intermittently
due to a race condition in the internal implementation of the JDK's
java.lang.reflect.Executable.getParameters() method.

This commit addresses this issue by creating instances of
SynthesizingMethodParameter via
SynthesizingMethodParameter.forExecutable(Executable, int) instead of
SynthesizingMethodParameter.forParameter(Parameter), since the latter
looks up the parameter index by iterating over the array returned by
Executable.getParameters() (which is not thread-safe).

Issue: SPR-17533

Issue: SPR-17486

Issue: SPR-17492

Issue: SPR-15540

(cherry picked from commit bf272b0b)

LocalResourceCache properly initializes cacheLimit on construction.

Issue: SPR-17527

(cherry picked from commit 262c702d)

Issue: SPR-17508

(cherry picked from commit f5aeb814)

Issue: SPR-17525

Issue: SPR-17518

See SPR-17502

Prior to this commit, when errors happened before the response was
committed, the `Content-Length` response header would be left as is.
This can be problematic since the error can be handled later in the
chain and the response body changed accordingly. For example, Spring
Boot renders error pages in those cases. If the `Content-Length` is set,
HTTP clients can get confused and only consider part of the error
response body.

This commit ensures that any `Content-Length` response header is removed
in case of errors, if the response is not already committed.

This is done at the `AbstractServerHttpResponse` level, since errors can
be handled in multiple places and the response itself is the safest
place to handle this case.

As a consequence, this commit also removes `Content-Length` checks in
`EncoderHttpMessageWriter` since we now consider that we should rely on
the response body we're about to write rather than any previously set
value.

Issue: SPR-17502
(Cherry-picked from 3203d398)

Issue: SPR-17501

Unlike 5,1, TEMPLATE_AND_VALUES is not the default encoding mode.
Nevertheless when that mode is used, it should work consistently.

Issue: SPR-17465

Issue: SPR-17473

Issue: SPR-14514
Issue: SPR-15600

Issue: SPR-17476

(cherry picked from commit 362c59c3)

Issue: SPR-17306

(cherry picked from commit 5e7a8b27)

Issue: SPR-17445

(cherry picked from commit ea3250c8)

Issue: SPR-17442

(cherry picked from commit b1f5f515)

Issue: SPR-17448

(cherry picked from commit 59fa647e)

Includes deprecation of NON_BRIDGED_METHODS constant.

Issue: SPR-17464

(cherry picked from commit 0a7dcf14)

Issue: SPR-17469

After the fix #658c7f for lenient parsing of dates, the error message
raised uses an HttpHeaders-formatted date. As a result the test
verifying the error message fails in the beginning of the month between
1-9 because it's formatted slightly differently.

Issue: SPR-16636

Issue: SPR-17374

(cherry picked from commit dc1e3b46)

Prior to this commit, no `ResourceUrlProvider` was configured
in WebFlux (no bean was contributed by the WebFlux infrastructure).
Also, several `ResourceTransformer` instances that extend the
`ResourceTransformerSupport` base class need a `ResourceUrlProvider`
to resolve absolute URLs when rewriting resource URLs. At this point,
no `ResourceUrlProvider` was configured and they could only resolve
relative URLs.

This commit contributes a new `ResourceUrlProvider` to the WebFlux
configuration; this bean can be reused by the WebFlux infrastructure and
application code.

This also automatically configure this shared `ResourceUrlProvider`
instance on the resource chain where needed.

Issue: SPR-17433
(Cherry-picked from fc957e95)