[Storage] Blob items are now shared between blobs. Ready for disk swap.

storage/browser/blob/blob_data_snapshot.cc

 // Copyright (c) 2015 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.
 
 #include "storage/browser/blob/blob_data_snapshot.h"
 
 namespace storage {
 
 BlobDataSnapshot::BlobDataSnapshot(
     const std::string& uuid,
     const std::string& content_type,
     const std::string& content_disposition,
     const std::vector<scoped_refptr<BlobDataItem>>& items)
     : uuid_(uuid),
       content_type_(content_type),
       content_disposition_(content_disposition),
       items_(items) {
 }
 
+BlobDataSnapshot::BlobDataSnapshot(const std::string& uuid,
+                                   const std::string& content_type,
+                                   const std::string& content_disposition)
+    : uuid_(uuid),
+      content_type_(content_type),
+      content_disposition_(content_disposition) {
+}
+
 BlobDataSnapshot::BlobDataSnapshot(const BlobDataSnapshot& other)
     : uuid_(other.uuid_),
       content_type_(other.content_type_),
       content_disposition_(other.content_disposition_),
       items_(other.items_) {
 }
 
 BlobDataSnapshot::~BlobDataSnapshot() {
 }
 
 size_t BlobDataSnapshot::GetMemoryUsage() const {
   int64 memory = 0;
   for (const auto& data_item : items_) {
     if (data_item->type() == DataElement::TYPE_BYTES)
       memory += data_item->length();
   }
   return memory;
 }
 
 }  // namespace storage