Catch and protect against when getHReturn() passes null to avoid NPE

ethereumj-core/src/main/java/org/ethereum/vm/ProgramResult.java

@@ -43,6 +43,8 @@ public class ProgramResult {
     }
 
     public ByteBuffer getHReturn() {
+        if (hReturn == null)
+           this.setHReturn(new byte[] {});
         return hReturn;
     }
 

ethereumj-core/src/test/java/test/ethereum/jsontestsuite/GitHubStateTest.java

@@ -44,7 +44,6 @@ public class GitHubStateTest {
     public void stInitCodeTest() throws ParseException { // [V]
 
         Set<String> excluded = new HashSet<>();
-        excluded.add("CallContractToCreateContractWhichWouldCreateContractInInitCode");
 
         String json = JSONReader.loadJSON("StateTests/stInitCodeTest.json");
         GitHubJSONTestSuite.runGitHubJsonStateTest(json, excluded);