Use a two-part data format version in IndexedDB metadata.

content/browser/indexed_db/indexed_db_fake_backing_store.cc

Index: content/browser/indexed_db/indexed_db_fake_backing_store.cc
diff --git a/content/browser/indexed_db/indexed_db_fake_backing_store.cc b/content/browser/indexed_db/indexed_db_fake_backing_store.cc
index d89073d9e51f4cbd1b5f8c03352ee047bd89d230..6465661bbf51b3323be68ac494d6a4a72f3fcef0 100644
--- a/content/browser/indexed_db/indexed_db_fake_backing_store.cc
+++ b/content/browser/indexed_db/indexed_db_fake_backing_store.cc
@@ -13,6 +13,7 @@ IndexedDBFakeBackingStore::IndexedDBFakeBackingStore()
     : IndexedDBBackingStore(NULL /* indexed_db_factory */,
                             url::Origin(GURL("http://localhost:81")),
                             base::FilePath(),
+                            IndexedDBDataFormatVersion(),
                             scoped_refptr<net::URLRequestContextGetter>(),
                             std::unique_ptr<LevelDBDatabase>(),
                             std::unique_ptr<LevelDBComparator>(),
@@ -23,6 +24,7 @@ IndexedDBFakeBackingStore::IndexedDBFakeBackingStore(
     : IndexedDBBackingStore(factory,
                             url::Origin(GURL("http://localhost:81")),
                             base::FilePath(),
+                            IndexedDBDataFormatVersion(),
                             NULL /* request_context */,
                             std::unique_ptr<LevelDBDatabase>(),
                             std::unique_ptr<LevelDBComparator>(),