[java] MethodReturnsInternalArray - add test case (#3630)

pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/bestpractices/xml/MethodReturnsInternalArray.xml

@@ -454,6 +454,28 @@ public interface Outer {
         String [] arr;
         String [] getArr() {return arr;}
     }
+}
+        ]]></code>
+    </test-code>
+
+    <test-code>
+        <description>[java] MethodReturnsInternalArray doesn't consider anonymous classes #3630</description>
+        <expected-problems>1</expected-problems>
+        <expected-linenumbers>7</expected-linenumbers>
+        <code><![CDATA[
+public class Outer {
+    private static final String[] names = new String[] {"a", "b"};
+    public static Provider getProvider() {
+        return new Provider() {
+            @Override
+            public String[] getNames() {
+                return names;
+            }
+        };
+    }
+    public interface Provider {
+        String[] getNames();
+    }
 }
         ]]></code>
     </test-code>