HV-1446 Remove UnconstrainedEntityMetaDataSingleton

We can't use it as it prevents to return proper errors when a property
or a method doesn't exist in a bean.

engine/src/main/java/org/hibernate/validator/internal/metadata/BeanMetaDataManager.java

@@ -22,7 +22,6 @@
 import org.hibernate.validator.internal.metadata.aggregated.BeanMetaData;
 import org.hibernate.validator.internal.metadata.aggregated.BeanMetaDataImpl;
 import org.hibernate.validator.internal.metadata.aggregated.BeanMetaDataImpl.BeanMetaDataBuilder;
-import org.hibernate.validator.internal.metadata.aggregated.UnconstrainedEntityMetaDataSingleton;
 import org.hibernate.validator.internal.metadata.core.AnnotationProcessingOptions;
 import org.hibernate.validator.internal.metadata.core.AnnotationProcessingOptionsImpl;
 import org.hibernate.validator.internal.metadata.core.ConstraintHelper;
@@ -153,8 +152,14 @@ public BeanMetaDataManager(ConstraintHelper constraintHelper,
 		this.metaDataProviders.add( defaultProvider );
 	}
 
+	@SuppressWarnings("unchecked")
 	public <T> BeanMetaData<T> getBeanMetaData(Class<T> beanClass) {
-		return getOrCreateBeanMetaData( beanClass, false );
+		Contracts.assertNotNull( beanClass, MESSAGES.beanTypeCannotBeNull() );
+
+		BeanMetaData<T> beanMetaData = (BeanMetaData<T>) beanMetaDataCache.computeIfAbsent( beanClass,
+				bc -> createBeanMetaData( bc ) );
+
+		return beanMetaData;
 	}
 
 	public void clear() {
@@ -199,39 +204,6 @@ private AnnotationProcessingOptions getAnnotationProcessingOptionsFromNonDefault
 		return options;
 	}
 
-	@SuppressWarnings("unchecked")
-	private <T> BeanMetaData<T> getOrCreateBeanMetaData(Class<T> beanClass, boolean allowUnconstrainedTypeSingleton) {
-		Contracts.assertNotNull( beanClass, MESSAGES.beanTypeCannotBeNull() );
-
-		BeanMetaData<T> beanMetaData = (BeanMetaData<T>) beanMetaDataCache.get( beanClass );
-
-		// create a new BeanMetaData in case none is cached
-		if ( beanMetaData == null ) {
-			beanMetaData = createBeanMetaData( beanClass );
-			if ( !beanMetaData.hasConstraints() && allowUnconstrainedTypeSingleton ) {
-				beanMetaData = (BeanMetaData<T>) UnconstrainedEntityMetaDataSingleton.getSingleton();
-			}
-
-			final BeanMetaData<T> cachedBeanMetaData = (BeanMetaData<T>) beanMetaDataCache.putIfAbsent(
-					beanClass,
-					beanMetaData
-			);
-			if ( cachedBeanMetaData != null ) {
-				beanMetaData = cachedBeanMetaData;
-			}
-		}
-
-		if ( beanMetaData instanceof UnconstrainedEntityMetaDataSingleton && !allowUnconstrainedTypeSingleton ) {
-			beanMetaData = createBeanMetaData( beanClass );
-			beanMetaDataCache.put(
-					beanClass,
-					beanMetaData
-			);
-		}
-
-		return beanMetaData;
-	}
-
 	/**
 	 * Returns a list with the configurations for all types contained in the given type's hierarchy (including
 	 * implemented interfaces) starting at the specified type.