Move WebDropData to content::DropData and split off conversion function.

content/renderer/drop_data_builder.h

Index: content/renderer/drop_data_builder.h
diff --git a/content/renderer/drop_data_builder.h b/content/renderer/drop_data_builder.h
new file mode 100644
index 0000000000000000000000000000000000000000..4870d47f9272c7f70775a38ed095e568728d7218
--- /dev/null
+++ b/content/renderer/drop_data_builder.h
@@ -0,0 +1,22 @@
+// Copyright 2013 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.
+
+#ifndef CONTENT_RENDERER_DROP_DATA_BUILDER_H_
+#define CONTENT_RENDERER_DROP_DATA_BUILDER_H_
+
+namespace WebKit {
+class WebDragData;
+}
+
+namespace content {
+struct DropData;
+
+class DropDataBuilder {
+ public:
+  static DropData Build(const WebKit::WebDragData& data);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_DROP_DATA_BUILDER_H_