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

content/common/indexed_db/indexed_db_struct_traits.h

Index: content/common/indexed_db/indexed_db_struct_traits.h
diff --git a/content/common/indexed_db/indexed_db_struct_traits.h b/content/common/indexed_db/indexed_db_struct_traits.h
index 913b56292647633bd0623a98038d77182e0dfdb3..42aa7f3c70937b9d16177c106f7bccda58abb62b 100644
--- a/content/common/indexed_db/indexed_db_struct_traits.h
+++ b/content/common/indexed_db/indexed_db_struct_traits.h
@@ -139,6 +139,21 @@ struct StructTraits<indexed_db::mojom::DatabaseMetadataDataView,
 };
 
 template <>
+struct StructTraits<indexed_db::mojom::DataFormatVersionDataView,
+                    content::IndexedDBDataFormatVersion> {
+  static uint64_t v8_version(
+      const content::IndexedDBDataFormatVersion& version) {
+    return version.v8_version();
+  }
+  static uint64_t blink_version(
+      const content::IndexedDBDataFormatVersion& version) {
+    return version.blink_version();
+  }
+  static bool Read(indexed_db::mojom::DataFormatVersionDataView data,
+                   content::IndexedDBDataFormatVersion* out);
+};
+
+template <>
 struct EnumTraits<indexed_db::mojom::CursorDirection,
                   blink::WebIDBCursorDirection> {
   static indexed_db::mojom::CursorDirection ToMojom(