This is the implementation of the primary and secondary blob journals for

content/browser/indexed_db/indexed_db_leveldb_coding.h

 // Copyright (c) 2013 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.
 
 #ifndef CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_LEVELDB_CODING_H_
 #define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_LEVELDB_CODING_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_piece.h"
 #include "content/common/indexed_db/indexed_db_key.h"
 #include "content/common/indexed_db/indexed_db_key_path.h"
 
 namespace content {
 
 CONTENT_EXPORT extern const unsigned char kMinimumIndexId;
 
 CONTENT_EXPORT std::string MaxIDBKey();
 CONTENT_EXPORT std::string MinIDBKey();
 
+// DatabaseId, BlobKey
+typedef std::pair<int64_t, int64_t> BlobJournalEntryType;
+typedef std::vector<BlobJournalEntryType> BlobJournalType;
+
 CONTENT_EXPORT void EncodeByte(unsigned char value, std::string* into);
 CONTENT_EXPORT void EncodeBool(bool value, std::string* into);
 CONTENT_EXPORT void EncodeInt(int64 value, std::string* into);
 CONTENT_EXPORT void EncodeVarInt(int64 value, std::string* into);
 CONTENT_EXPORT void EncodeString(const base::string16& value,
                                  std::string* into);
 CONTENT_EXPORT void EncodeStringWithLength(const base::string16& value,
                                            std::string* into);
 CONTENT_EXPORT void EncodeBinary(const std::string& value, std::string* into);
 CONTENT_EXPORT void EncodeDouble(double value, std::string* into);
 CONTENT_EXPORT void EncodeIDBKey(const IndexedDBKey& value, std::string* into);
 CONTENT_EXPORT void EncodeIDBKeyPath(const IndexedDBKeyPath& value,
                                      std::string* into);
+CONTENT_EXPORT void EncodeBlobJournal(const BlobJournalType& journal,
+                                      std::string* into);
 
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeByte(base::StringPiece* slice,
                                                   unsigned char* value);
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeBool(base::StringPiece* slice,
                                                   bool* value);
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeInt(base::StringPiece* slice,
                                                  int64* value);
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeVarInt(base::StringPiece* slice,
                                                     int64* value);
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeString(base::StringPiece* slice,
                                                     base::string16* value);
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeStringWithLength(
     base::StringPiece* slice,
     base::string16* value);
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeBinary(base::StringPiece* slice,
                                                     std::string* value);
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeDouble(base::StringPiece* slice,
                                                     double* value);
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeIDBKey(
     base::StringPiece* slice,
     scoped_ptr<IndexedDBKey>* value);
 CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeIDBKeyPath(
     base::StringPiece* slice,
     IndexedDBKeyPath* value);
+CONTENT_EXPORT WARN_UNUSED_RESULT bool DecodeBlobJournal(
+    base::StringPiece* slice,
+    BlobJournalType* journal);
 
 CONTENT_EXPORT int CompareEncodedStringsWithLength(base::StringPiece* slice1,
                                                    base::StringPiece* slice2,
                                                    bool* ok);
 
 CONTENT_EXPORT WARN_UNUSED_RESULT bool ExtractEncodedIDBKey(
     base::StringPiece* slice,
     std::string* result);
 
 CONTENT_EXPORT int CompareEncodedIDBKeys(base::StringPiece* slice1,
@@ skipping 401 matching lines @@
   std::string encoded_user_key_;
   std::string encoded_primary_key_;
   int64 sequence_number_;
 
   DISALLOW_COPY_AND_ASSIGN(IndexDataKey);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_LEVELDB_CODING_H_