Remove usage of FOR_EACH_OBSERVER macro in components/signin

components/signin/core/browser/signin_manager_base.cc

Index: components/signin/core/browser/signin_manager_base.cc
diff --git a/components/signin/core/browser/signin_manager_base.cc b/components/signin/core/browser/signin_manager_base.cc
index efbb7e4ad41e2b87901475ca0ed6307fb060be97..68d68b477b4334edc4d004773f9daa798cc5621d 100644
--- a/components/signin/core/browser/signin_manager_base.cc
+++ b/components/signin/core/browser/signin_manager_base.cc
@@ -250,7 +250,6 @@ void SigninManagerBase::RemoveSigninDiagnosticsObserver(
 void SigninManagerBase::NotifyDiagnosticsObservers(
     const TimedSigninStatusField& field,
     const std::string& value) {
-  FOR_EACH_OBSERVER(SigninDiagnosticsObserver,
-                    signin_diagnostics_observers_,
-                    NotifySigninValueChanged(field, value));
+  for (auto& observer : signin_diagnostics_observers_)
+    observer.NotifySigninValueChanged(field, value);
 }