Reduce the memory usage of bookmarks storage

components/bookmarks/browser/bookmark_codec.h

Index: components/bookmarks/browser/bookmark_codec.h
diff --git a/components/bookmarks/browser/bookmark_codec.h b/components/bookmarks/browser/bookmark_codec.h
index 7760826e4f61d7769fe907a2b9f639f5e953e211..8b69bcc548bf830e117506af2b97bbba4d1c28e3 100644
--- a/components/bookmarks/browser/bookmark_codec.h
+++ b/components/bookmarks/browser/bookmark_codec.h
@@ -10,6 +10,7 @@
 #include <memory>
 #include <set>
 #include <string>
+#include <vector>
 
 #include "base/macros.h"
 #include "base/md5.h"
@@ -87,6 +88,10 @@ class BookmarkCodec {
   // false after encoding.
   bool ids_reassigned() const { return ids_reassigned_; }
 
+  void set_excluded_meta_info_keys(const std::vector<std::string>& keys) {
+    excluded_meta_info_keys_ = keys;
+  }
+
   // Names of the various keys written to the Value.
   static const char kRootsKey[];
   static const char kRootFolderNameKey[];
@@ -205,6 +210,8 @@ class BookmarkCodec {
   // Sync transaction version set on bookmark model root.
   int64_t model_sync_transaction_version_;
 
+  std::vector<std::string> excluded_meta_info_keys_;
+
   DISALLOW_COPY_AND_ASSIGN(BookmarkCodec);
 };