title: QML DropArea accept external drag
body: <p>I've noticed a new DropArea component in Qt5. I'm trying to drag a file from Finder (Mac) but only onEntered method is called.</p>
  
  <pre><code>import QtQuick 2.0
  
  Rectangle {
      id: background;
      color: "white";
      width: 300;
      height: 300;
  
      DropArea {
          id: dropArea;
          anchors.fill: parent;
          onEntered: {
              background.color = "gray";
              drag.accept (Qt.CopyAction);
              console.log("onEntered");
          }
          onDropped: {
              console.log ("onDropped");
          }
          onExited: {
              bckground.color = "white";
              console.log ("onExited");
          }
      }
  }
  </code></pre>
  
  <p>and here is window creation code:</p>
  
  <pre><code>int main(int argc, char *argv[])
  {
      QApplication a(argc, argv);
  
      QQuickView qmlView;
      qmlView.setGeometry(0, 200, 600, 400);
      qmlView.setResizeMode (QQuickView::SizeRootObjectToView);
      qmlView.setSource(QUrl::fromLocalFile("/Users/ivann/Projects/QtGuiTestApp/testView.qml"));
      qmlView.show();
  
      return a.exec();
  }
  </code></pre>
  
  <p>Am I missing something?</p>