Pass implementation object to supplemental classes by reference

Source/web/WebDragData.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 124 matching lines @@
     DraggedIsolatedFileSystem* filesystem = DraggedIsolatedFileSystem::from(m_private);
     if (filesystem)
         return filesystem->filesystemId();
     return WebString();
 }
 
 void WebDragData::setFilesystemId(const WebString& filesystemId)
 {
     // The ID is an opaque string, given by and validated by chromium port.
     ensureMutable();
-    DraggedIsolatedFileSystem::provideTo(m_private, DraggedIsolatedFileSystem::supplementName(), DraggedIsolatedFileSystem::create(filesystemId));
+    ASSERT(m_private);
+    DraggedIsolatedFileSystem::provideTo(*m_private, DraggedIsolatedFileSystem::supplementName(), DraggedIsolatedFileSystem::create(filesystemId));
 }
 
 WebDragData::WebDragData(const WTF::PassRefPtr<WebCore::DataObject>& data)
     : m_private(static_cast<WebDragDataPrivate*>(data.leakRef()))
 {
 }
 
 WebDragData& WebDragData::operator=(const WTF::PassRefPtr<WebCore::DataObject>& data)
 {
     assign(static_cast<WebDragDataPrivate*>(data.leakRef()));
@@ skipping 13 matching lines @@
     m_private = p;
 }
 
 void WebDragData::ensureMutable()
 {
     ASSERT(!isNull());
     ASSERT(m_private->hasOneRef());
 }
 
 } // namespace blink