[BlobAsync] Disk support for blob storage

storage/browser/blob/shareable_blob_data_item.cc

Index: storage/browser/blob/shareable_blob_data_item.cc
diff --git a/storage/browser/blob/shareable_blob_data_item.cc b/storage/browser/blob/shareable_blob_data_item.cc
index 40aaf9c7e10d29d40acbc73798f67f6c16030b4d..2de6f8dd3895237fa108f15b139da02d4f6e8e73 100644
--- a/storage/browser/blob/shareable_blob_data_item.cc
+++ b/storage/browser/blob/shareable_blob_data_item.cc
@@ -7,13 +7,18 @@
 #include "storage/browser/blob/blob_data_item.h"
 
 namespace storage {
+namespace {
 
-ShareableBlobDataItem::ShareableBlobDataItem(
-    const std::string& blob_uuid,
-    const scoped_refptr<BlobDataItem>& item)
-    : item_(item) {
+uint64_t GetAndIncrementItemId() {
+  static uint64_t sNextItemId = 0;
+  return sNextItemId++;
+}
+
+}  // namespace
+
+ShareableBlobDataItem::ShareableBlobDataItem(scoped_refptr<BlobDataItem> item)
+    : item_id_(GetAndIncrementItemId()), item_(std::move(item)) {
   DCHECK_NE(item_->type(), DataElement::TYPE_BLOB);
-  referencing_blobs_.insert(blob_uuid);
 }
 
 ShareableBlobDataItem::~ShareableBlobDataItem() {