These helpers to convert between std::map and base::flat_map were added during the rebase from Cr79 to Cr80 (see [1]) in order to keep Brave building after such helpers were removed from where they used to live in upstream Chromium, inside of Mojo. This patch adapts all the code that depended on such functions not to require them and removes this utils.h file, so that we no longer depend on such conversions. [1] https://github.com/brave/brave-core/commit/8d63987e