IdentityManager::OnRefreshTokenRemovedForAccount() expects as a first parameter a "const std::string&" instead of a "const AccountInfo&", but the override IdentityManagerObserverBridge::OnRefreshTokenRemovedForAccount() declares a const AccountInfo& instead, resulting in the following build failure when trying to use this new class (e.g. in CL 1326151):

    In file included from ../../services/identity/public/objc/identity_manager_observer_bridge.mm:5:
    ../../services/identity/public/objc/identity_manager_observer_bridge.h:52:40: error: non-virtual member function marked 'override' hides virtual member function
          const AccountInfo& account_info) override;                          
                                           ^
    ../../services/identity/public/cpp/identity_manager.h:101:18: note: hidden overloaded virtual function 'identity::IdentityManager::Observer::OnRefreshTokenRemovedForAccount' declared here: type mismatch at 1st p
    arameter ('const std::string &' (aka 'const basic_string<char, char_traits<char>, allocator<char> > &') vs 'const AccountInfo &')
        virtual void OnRefreshTokenRemovedForAccount(                                                
                     ^
    1 error generated.
    [3/12] OBJCXX obj/ios/chrome/browser/ui/bookmarks/bookmarks/bookmark_promo_controller.o
    FAILED: obj/ios/chrome/browser/ui/bookmarks/bookmarks/bookmark_promo_controller.o


This new IdentityManagerObserverBridge API has been recently introduced as part of CL 1203934, but nothing uses it yet so I suppose that's why this run undetected until I tried to use it now to migrate bookmark_promo_controller.mm as part of CL 1326151.

Filing this issue so that I can attach a CL for it that I need to migrate bookmark_promo_controller.mm.

//cc @blundell & @jlebel