HttpHeaders fails getAllow if set to EmptyCollection

Prior to this commit, calls to getAllow would fail is setAllow was set
to an EmptyCollection right before.

    java.lang.IllegalArgumentException: No enum constant
    org.springframework.http.HttpMethod

This commit fixes this by testing the header value for an empty value
before trying to use it to get a value from the Enum.

Issue: SPR-11917
(cherry picked from commit 9054f4f)
WebSphereUowTransactionManager exposes SmartTransactionObject

Issue: SPR-11876
(cherry picked from commit a0c86ae)
MBeanExportConfiguration's SpecificPlatform properly calls afterPropertiesSet

Issue: SPR-11877
(cherry picked from commit 0a34f86)
PathMatchingResourcePatternResolver's findPathMatchingResources needs to check for VFS before checking isJarResource

ResourceUtils isFileURL also detects "vfsfile" as a file system protocol (again).

Issue: SPR-11887
(cherry picked from commit 8ddbbc2)
FrameworkPortlet properly initializes StandardPortletEnvironment's property sources and exposes local PortletRequestAttributes in case of pre-bound ServletRequestAttributes as well

Issue: SPR-11816
Issue: SPR-11295
(cherry picked from commit 7d94b5e)
UriComponentBuilder allows for multiple independent build() calls on same builder instance

Issue: SPR-11885
(cherry picked from commit c73ac07)
Cache Class.getDeclaredMethods() results and avoid pattern matching in isCglibRenamedMethod as far as possible

Issue: SPR-11882
Issue: SPR-11894
(cherry picked from commit 5f695a4)
AbstractAutowireCapableBeanFactory's createBean/autowireBean/configureBean use CacheUtils.isCacheSafe to re-enable PropertyDescriptor caching

Issue: SPR-11875
(cherry picked from commit c32d559)
Consistent declaration of private static final logger variables

Issue: SPR-11905
(cherry picked from commit c16032b)
Polishing (backported from master)
(cherry picked from commit 48f753f)
Upgrade to ASM 5.0.3 (and Hibernate 4.2.14)

Issue: SPR-11889