Refactoring: Introduce HTMLImport interface to form import tree.

Source/core/html/HTMLImport.h

Index: Source/core/html/HTMLImport.h
diff --git a/Source/core/platform/Partitions.h b/Source/core/html/HTMLImport.h
similarity index 83%
copy from Source/core/platform/Partitions.h
copy to Source/core/html/HTMLImport.h
index 56be59a1bacb75083e4af69d17fb3c97e09a0d51..a31c3d32c795aaa002a2f7f24597dc7fa73b33c0 100644
--- a/Source/core/platform/Partitions.h
+++ b/Source/core/html/HTMLImport.h
@@ -28,24 +28,25 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef Partitions_h
-#define Partitions_h
-
-#include "wtf/PartitionAlloc.h"
+#ifndef HTMLImport_h
+#define HTMLImport_h
 
 namespace WebCore {
 
-class Partitions {
+class Document;
+class HTMLImportsController;
+
+class HTMLImport {
 public:
-    static void init();
-    static void shutdown();
+    virtual ~HTMLImport() { }
 
-    ALWAYS_INLINE static PartitionRoot* getObjectModelPartition() { return &m_objectModelRoot; }
+    bool haveChildrenLoaded();
 
-private:
-    static PartitionRoot m_objectModelRoot;
+    virtual HTMLImportsController* controller() = 0;
+    virtual HTMLImport* parent() = 0;
+    virtual Document* document() = 0;
 };
 
 } // namespace WebCore
 
-#endif // Partitions_h
+#endif // HTMLImport_h