JDR: do not create package fragment for class statics if class cannot be resolved

This keeps behaviour consistent in rare cases when JavaClass can be found but not resolved
As of now this can happen in IDE if we take PsiClass from index but file structure is wrong so we can't resolve the class
Add test which documents this case

idea/testData/resolve/referenceToJavaWithWrongFileStructure/ClassStatics.java

@@ -0,0 +1,5 @@
+package wrong;
+
+public class ClassStatics {
+    public static void staticMethod() {}
+}