Add glue for supporting custom MIME types in DataTransfer.

webkit/glue/webdropdata.h

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // A struct for managing data being dropped on a webview.  This represents a
 // union of all the types of data that can be dropped in a platform neutral
 // way.
 
 #ifndef WEBKIT_GLUE_WEBDROPDATA_H_
 #define WEBKIT_GLUE_WEBDROPDATA_H_
 
+#include <map>
 #include <string>
 #include <vector>
 
 #include "base/string16.h"
 #include "googleurl/src/gurl.h"
 
 struct IDataObject;
 
 namespace WebKit {
 class WebDragData;
@@ skipping 26 matching lines @@
   // User is dragging text/html into the webview (e.g., out of Firefox).
   // |html_base_url| is the URL that the html fragment is taken from (used to
   // resolve relative links).  It's ok for |html_base_url| to be empty.
   string16 text_html;
   GURL html_base_url;
 
   // User is dragging data from the webview (e.g., an image).
   string16 file_description_filename;
   std::string file_contents;
 
+  std::map<string16, string16> custom_data;

[tony, 2011/12/02 00:13:29]

Hmm, I guess since the API is from javascript, there's no easy way to put bytes
into the clipboard for other apps to consume.  That seems like a pretty big
limitation of custom data types, but I guess that can be addressed in future
versions of the spec?

[dcheng, 2011/12/02 00:29:17]

Given the APIs available on Windows/Linux, we can't safely expose those APIs to
the web, even with attempts to set a limit of x per domain, since these
resources aren't reclaimable. It's definitely not ideal, hopefully the native
APIs improve.

+
   // Convert to a WebDragData object.
   WebKit::WebDragData ToDragData() const;
 
   // Helper method for converting Window's specific IDataObject to a WebDropData
   // object.  TODO(tc): Move this to the browser side since it's Windows
   // specific and no longer used in webkit.
   static void PopulateWebDropData(IDataObject* data_object,
                                   WebDropData* drop_data);
 };
 
 #endif  // WEBKIT_GLUE_WEBDROPDATA_H_