Fixed WebDragData's wrong dependency.

Source/web/WebDragData.cpp

Index: Source/web/WebDragData.cpp
diff --git a/Source/web/WebDragData.cpp b/Source/web/WebDragData.cpp
index e2005f5250a162abb56f94fed3eaddb89d315fd3..9125cc15f8054693389a403df7bc0a6034d7155d 100644
--- a/Source/web/WebDragData.cpp
+++ b/Source/web/WebDragData.cpp
@@ -60,22 +60,6 @@ void WebDragData::assign(const WebDragData& other)
     m_private = other.m_private;
 }
 
-WebDragData::WebDragData(const PassRefPtrWillBeRawPtr<DataObject>& object)
-{
-    m_private = object;
-}
-
-WebDragData& WebDragData::operator=(const PassRefPtrWillBeRawPtr<DataObject>& object)
-{
-    m_private = object;
-    return *this;
-}
-
-DataObject* WebDragData::getValue() const
-{
-    return m_private.get();
-}
-
 void WebDragData::ensureMutable()
 {
     ASSERT(!isNull());