diff -r 000000000000 -r 6474c204b198 content/base/src/nsContentAreaDragDrop.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/base/src/nsContentAreaDragDrop.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,83 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#ifndef nsContentAreaDragDrop_h__
+#define nsContentAreaDragDrop_h__
+
+
+#include "nsCOMPtr.h"
+
+#include "nsIDOMEventListener.h"
+#include "nsITransferable.h"
+
+class nsIDOMNode;
+class nsPIDOMWindow;
+class nsIDOMDragEvent;
+class nsISelection;
+class nsITransferable;
+class nsIContent;
+class nsIURI;
+class nsIFile;
+class nsISimpleEnumerator;
+
+namespace mozilla {
+namespace dom {
+class DataTransfer;
+}
+}
+
+//
+// class nsContentAreaDragDrop, used to generate the dragdata
+//
+class nsContentAreaDragDrop
+{
+public:
+
+  /**
+   * Determine what data in the content area, if any, is being dragged.
+   *
+   * aWindow - the window containing the target node
+   * aTarget - the mousedown event target that started the drag
+   * aSelectionTargetNode - the node where the drag event should be fired
+   * aIsAltKeyPressed - true if the Alt key is pressed. In some cases, this
+   *                    will prevent the drag from occuring. For example,
+   *                    holding down Alt over a link should select the text,
+   *                    not drag the link.
+   * aDataTransfer - the dataTransfer for the drag event.
+   * aCanDrag - [out] set to true if the drag may proceed, false to stop the
+   *            drag entirely
+   * aSelection - [out] set to the selection being dragged, or null if no
+   *                    selection is being dragged.
+   * aDragNode - [out] the link, image or area being dragged, or null if the
+   *             drag occurred on another element.
+   */
+  static nsresult GetDragData(nsPIDOMWindow* aWindow,
+                              nsIContent* aTarget,
+                              nsIContent* aSelectionTargetNode,
+                              bool aIsAltKeyPressed,
+                              mozilla::dom::DataTransfer* aDataTransfer,
+                              bool* aCanDrag,
+                              nsISelection** aSelection,
+                              nsIContent** aDragNode);
+};
+
+// this is used to save images to disk lazily when the image data is asked for
+// during the drop instead of when it is added to the drag data transfer. This
+// ensures that the image data is only created when an image drop is allowed.
+class nsContentAreaDragDropDataProvider : public nsIFlavorDataProvider
+{
+public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIFLAVORDATAPROVIDER
+
+  virtual ~nsContentAreaDragDropDataProvider() {}
+
+  nsresult SaveURIToFile(nsAString& inSourceURIString,
+                         nsIFile* inDestFile, bool isPrivate);
+};
+
+
+#endif /* nsContentAreaDragDrop_h__ */
+