JS: use inheritance in js/mixed-static-instance-this-access

javascript/ql/test/query-tests/Declarations/MixedStaticInstanceThisAccess/MixedStaticInstanceThisAccess.expected

@@ -1,2 +1,3 @@
 | instanceStatic.js:3:9:3:16 | this.baz | Access to instance method $@ from static method $@ is not possible through `this`. | instanceStatic.js:5:5:7:5 | baz(){\\n\\n    } | baz | instanceStatic.js:2:5:4:5 | static  ... K\\n    } | bar |
 | staticInstance.js:3:9:3:16 | this.baz | Access to static method $@ from instance method $@ is not possible through `this`. | staticInstance.js:5:5:6:5 | static baz(){\\n    } | baz | staticInstance.js:2:5:4:5 | bar(){\\n ... K\\n    } | bar |
+| tst.js:66:9:66:14 | this.f | Access to instance method $@ from static method $@ is not possible through `this`. | tst.js:60:5:62:5 | f() {\\n\\n    } | f | tst.js:65:5:67:5 | static  ... K\\n    } | test |

javascript/ql/test/query-tests/Declarations/MixedStaticInstanceThisAccess/tst.js

@@ -41,3 +41,28 @@ class C4 {
     }
 }
 C4.f = x;
+
+class C5_super {
+    f() {
+
+    }
+}
+class C5 extends C5_super{
+    static f() {
+
+    }
+    test() {
+        this.f; // OK
+    }
+}
+
+class C6_super {
+    f() {
+
+    }
+}
+class C6 extends C6_super{
+    static test() {
+        this.f; // NOT OK
+    }
+}