Converter tests:

Change test data files extension to "java"

j2k/tests/testData/ast/callChainExpression/libraryMethodCallFromInstance.java

@@ -0,0 +1,17 @@
+//file
+class Library {
+  void call() {}
+
+  String getString() { return ""; }
+}
+
+class User {
+  void main() {
+    Library lib = new Library();
+    lib.call();
+    lib.getString().isEmpty();
+
+    new Library().call();
+    new Library().getString().isEmpty();
+  }
+}