Add LinkJavaScript::createObject

Creates an Object that represents a a LinkJavaScript with the given text
diff --git a/poppler/Link.cc b/poppler/Link.cc
index 5a5e868..bbba89c 100644
--- a/poppler/Link.cc
+++ b/poppler/Link.cc
@@ -823,6 +823,15 @@
   }
 }
 
+Object LinkJavaScript::createObject(XRef *xref, const GooString &js)
+{
+  Dict *linkDict = new Dict(xref);
+  linkDict->add("S", Object(objName, "JavaScript"));
+  linkDict->add("JS", Object(js.copy()));
+
+  return Object(linkDict);
+}
+
 //------------------------------------------------------------------------
 // LinkOCGState
 //------------------------------------------------------------------------
diff --git a/poppler/Link.h b/poppler/Link.h
index c1079bd..d610fad 100644
--- a/poppler/Link.h
+++ b/poppler/Link.h
@@ -427,6 +427,8 @@
   LinkActionKind getKind() const override { return actionJavaScript; }
   const GooString *getScript() const { return js; }
 
+  static Object createObject(XRef *xref, const GooString &js);
+
 private:
 
   GooString *js;