method refs: mark method as registered in RefCountHolder

java/java-impl/src/com/intellij/codeInsight/daemon/impl/analysis/HighlightVisitorImpl.java

@@ -967,6 +967,16 @@ public class HighlightVisitorImpl extends JavaElementVisitor implements Highligh
   @Override
   public void visitMethodReferenceExpression(PsiMethodReferenceExpression expression) {
     myHolder.add(HighlightUtil.checkMethodReferencesFeature(expression));
+    JavaResolveResult result;
+    try {
+      result = expression.advancedResolve(true);
+    }
+    catch (IndexNotReadyException e) {
+      return;
+    }
+    if (myRefCountHolder != null) {
+      myRefCountHolder.registerReference(expression, result);
+    }
   }
 
   @Override

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advHighlighting7/UsedMethodsByMethodReferences.java

@@ -0,0 +1,12 @@
+class C {
+  interface Simplest {
+    void m();
+  }
+  private static void simplest1() { }
+  private static void <warning descr="Private method 'simplest()' is never used">simplest</warning>() { }
+
+  public static void main(String[] args) {
+    Simplest o = C::simplest1;
+    System.out.println(o);
+  }
+}

java/java-tests/testSrc/com/intellij/codeInsight/daemon/LightAdvHighlightingJdk7Test.java

@@ -160,5 +160,6 @@ public class LightAdvHighlightingJdk7Test extends LightDaemonAnalyzerTestCase {
   public void testClassLiteral() throws Exception { doTest(false, false); }
   public void testExtensionMethods() throws Exception { doTest(false, false); }
   public void testMethodReferences() throws Exception { doTest(false, true, false); }
+  public void testUsedMethodsByMethodReferences() throws Exception { doTest(true, true, false); }
   public void testLambdaExpressions() throws Exception { doTest(false, true, false); }
 }