Nullablility diagnostics for extension functions

idea/tests/org/jetbrains/jet/JetTestUtils.java

@@ -2,7 +2,6 @@ package org.jetbrains.jet;
 
 import com.intellij.psi.PsiElement;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.jet.codegen.ClassCodegen;
 import org.jetbrains.jet.lang.ErrorHandler;
 import org.jetbrains.jet.lang.JetDiagnostic;
 import org.jetbrains.jet.lang.descriptors.*;
@@ -136,7 +135,7 @@ public class JetTestUtils {
 
                 @Override
                 public DeclarationDescriptor resolveReferenceExpression(JetReferenceExpression referenceExpression) {
-                    throw new UnsupportedOperationException(); // TODO
+                    return null;
                 }
 
                 @Override

idea/tests/org/jetbrains/jet/parsing/JetParsingTest.java

@@ -52,10 +52,10 @@ public class JetParsingTest extends ParsingTestCase {
     protected void checkResult(@NonNls String targetDataName, PsiFile file) throws IOException {
         file.acceptChildren(new JetVisitor() {
             @Override
-            public void visitJetElement(JetElement elem) {
-                elem.acceptChildren(this);
+            public void visitJetElement(JetElement element) {
+                element.acceptChildren(this);
                 try {
-                    checkPsiGetters(elem);
+                    checkPsiGetters(element);
                 } catch (Throwable throwable) {
                     throw new RuntimeException(throwable);
                 }