[Blob] Blob paging to disk patch.

storage/browser/blob/blob_data_item.h

Index: storage/browser/blob/blob_data_item.h
diff --git a/storage/browser/blob/blob_data_item.h b/storage/browser/blob/blob_data_item.h
index 9de0be91539969532f0a0ca2381bb495e0d7fec1..fb20212ea0a5fee0b40427f799945b80c5955500 100644
--- a/storage/browser/blob/blob_data_item.h
+++ b/storage/browser/blob/blob_data_item.h
@@ -62,6 +62,7 @@ class STORAGE_EXPORT BlobDataItem : public base::RefCounted<BlobDataItem> {
   friend class BlobDataBuilder;
   friend class BlobStorageContext;
   friend class base::RefCounted<BlobDataItem>;
+  friend class BlobMemoryController;
   friend STORAGE_EXPORT void PrintTo(const BlobDataItem& x, ::std::ostream* os);
 
   explicit BlobDataItem(scoped_ptr<DataElement> item);
@@ -80,6 +81,11 @@ class STORAGE_EXPORT BlobDataItem : public base::RefCounted<BlobDataItem> {
   // instance for disk cache entries during the lifetime of this BlobDataItem.
   disk_cache::Entry* disk_cache_entry_;
   int disk_cache_stream_index_;  // For TYPE_DISK_CACHE_ENTRY.
+
+  // This is a temporary file from the Blob system, and we need to call
+  // DecrementTempFileRefCount on the BlobMemoryController when this item
+  // is destructed.
+  bool temp_file_;
 };
 
 STORAGE_EXPORT bool operator==(const BlobDataItem& a, const BlobDataItem& b);