disable static method call on subclass if method is from interface

added in java 8, static methods in interfaces can't be called on subclasses, corresponding highlighting error provides the same fix and thus inspection is redundant

plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/bugs/StaticCallOnSubclassInspection.java

@@ -156,7 +156,7 @@ public class StaticCallOnSubclassInspection extends BaseInspection implements Cl
       if (declaringClass == null) {
         return;
       }
-      if (declaringClass.equals(referencedClass)) {
+      if (declaringClass.equals(referencedClass) || declaringClass.isInterface()) {
         return;
       }
       final PsiResolveHelper resolveHelper = JavaPsiFacade.getInstance(methodExpression.getProject()).getResolveHelper();

plugins/InspectionGadgets/test/com/siyeh/igfixes/bugs/staticCallOnSubclass/OnInterface.java

@@ -0,0 +1,13 @@
+
+interface I {
+    static <Z> void FOO() {
+
+    }
+}
+
+class A implements I  {
+    {
+        A.<String>F<caret>OO();
+    }
+}
+

plugins/InspectionGadgets/testsrc/com/siyeh/ig/fixes/bugs/StaticCallOnSubclassTest.java

@@ -33,6 +33,10 @@ public class StaticCallOnSubclassTest extends IGQuickFixesTestCase {
   public void testMethodReference() {
     doTest("methodRef", InspectionGadgetsBundle.message("static.method.via.subclass.rationalize.quickfix"));
   }
+  
+  public void testOnInterface() {
+    assertQuickfixNotAvailable(InspectionGadgetsBundle.message("static.method.via.subclass.rationalize.quickfix"));
+  }
 
   @Override
   protected String getRelativePath() {