SEC-1885: Change SecurityDebugBeanFactoryPostProcessor to only interact with BeanDefinitions rather than instances to prevent premature instatiation of FilterChainProxy and its dependencies

This issue occurred because the AutowiredAnnotationBeanPostProcessor had not been registered when the SecurityDebugBeanFactoryPostProcessor tried to obtain the FilterChainProxy. This caused
all of the FilterChainProxy's dependant beans to be resolved and if they used @Autowired they would not get processed properly.

config/src/test/java/org/springframework/security/config/util/InMemoryXmlApplicationContext.java

@@ -12,11 +12,13 @@ import org.springframework.security.util.InMemoryResource;
 public class InMemoryXmlApplicationContext extends AbstractXmlApplicationContext {
     private static final String BEANS_OPENING =
                     "<b:beans xmlns='http://www.springframework.org/schema/security'\n" +
+                    "    xmlns:context='http://www.springframework.org/schema/context'\n" +
                     "    xmlns:b='http://www.springframework.org/schema/beans'\n" +
                     "    xmlns:aop='http://www.springframework.org/schema/aop'\n" +
                     "    xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'\n" +
                     "    xsi:schemaLocation='http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd\n" +
                     "http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd\n" +
+                    "http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd\n" +
                     "http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security-";
     private static final String BEANS_CLOSE = "</b:beans>\n";