Converter tests:

Change test data files extension to "java"

j2k/tests/testData/ast/issues/kt-809.java

@@ -0,0 +1,22 @@
+//file
+package demo;
+
+class Container {
+  int myInt = 1;
+}
+
+class One {
+  static Container myContainer = new Container();
+}
+
+class IntContainer {
+  IntContainer(int i) {}
+}
+
+class Test {
+  void putInt(int i) { }
+  void test() {
+    putInt(One.myContainer.myInt);
+    new IntContainer(One.myContainer.myInt);
+  }
+}