Relaxed getElementTypeDescriptor assertion to not insist on a ResolvableType-known array

Issue: SPR-11608

spring-core/src/main/java/org/springframework/core/convert/TypeDescriptor.java

@@ -325,9 +325,7 @@ public class TypeDescriptor implements Serializable {
 		if (this.resolvableType.isArray()) {
 			return new TypeDescriptor(this.resolvableType.getComponentType(), null, this.annotations);
 		}
-		Assert.state(isCollection(), "Not an array or java.util.Collection");
 		return getRelatedIfResolvable(this, this.resolvableType.asCollection().getGeneric());
-
 	}
 
 	/**

spring-core/src/test/java/org/springframework/core/convert/support/DefaultConversionTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -53,7 +53,8 @@ import static org.junit.Assert.*;
  */
 public class DefaultConversionTests {
 
-	private DefaultConversionService conversionService = new DefaultConversionService();
+	private final DefaultConversionService conversionService = new DefaultConversionService();
+
 
 	@Test
 	public void testStringToCharacter() {
@@ -777,6 +778,16 @@ public class DefaultConversionTests {
 		assertThat(converted, equalTo(new char[] { 'a', 'b', 'c' }));
 	}
 
+	@Test
+	public void multidimensionalArrayToListConversionShouldConvertEntriesCorrectly() {
+		String[][] grid = new String[][] { new String[] { "1", "2", "3", "4" }, new String[] { "5", "6", "7", "8" },
+				new String[] { "9", "10", "11", "12" } };
+		List<String[]> converted = conversionService.convert(grid, List.class);
+		String[][] convertedBack = conversionService.convert(converted, String[][].class);
+		assertArrayEquals(grid, convertedBack);
+	}
+
+
 	public static class TestEntity {
 
 		private Long id;
@@ -794,6 +805,7 @@ public class DefaultConversionTests {
 		}
 	}
 
+
 	private static class ListWrapper {
 
 		private List<?> list;
@@ -807,8 +819,10 @@ public class DefaultConversionTests {
 		}
 	}
 
+
 	public Object assignableTarget;
 
+
 	private static class SSN {
 
 		private String value;
@@ -837,6 +851,7 @@ public class DefaultConversionTests {
 		}
 	}
 
+
 	private static class ISBN {
 
 		private String value;