Spring Framework 3.2 M2 added the ability to map requests using only
file extensions registered through the configured through a
ContentNeotiationManager, as opposed to allowing any file extension
(i.e. ".*"). The MVC namespace the MVC Java config automatically
register extensions such as ".json" and ".xml" depending on libraries
found on the classpath. That in turn causes issues in cases where
additional extensions are in use but not registered (e.g. ".html").
This change ensures that matching with registered file extensions only
works only if explicitly enabled through a property on
RequestMappingHandlerMapping.
Issue: SPR-10061, SPR-8474
9cc4bd892a