Reduce usage of FOR_EACH_OBSERVER macro in chrome/browser

chrome/browser/local_discovery/service_discovery_client_mdns.cc

Index: chrome/browser/local_discovery/service_discovery_client_mdns.cc
diff --git a/chrome/browser/local_discovery/service_discovery_client_mdns.cc b/chrome/browser/local_discovery/service_discovery_client_mdns.cc
index cb8ff2e7f4fb9fee2a17f739bf13b332727131d1..7e7ca7fed50f0b1124fe04c4904327bcfe9f759a 100644
--- a/chrome/browser/local_discovery/service_discovery_client_mdns.cc
+++ b/chrome/browser/local_discovery/service_discovery_client_mdns.cc
@@ -426,7 +426,8 @@ void ServiceDiscoveryClientMdns::OnMdnsInitialized(bool success) {
 
   // Initialization is done, no need to delay tasks.
   need_dalay_mdns_tasks_ = false;
-  FOR_EACH_OBSERVER(Proxy, proxies_, OnNewMdnsReady());
+  for (Proxy& observer : proxies_)
+    observer.OnNewMdnsReady();
 }
 
 void ServiceDiscoveryClientMdns::ReportSuccess() {
@@ -438,7 +439,8 @@ void ServiceDiscoveryClientMdns::ReportSuccess() {
 void ServiceDiscoveryClientMdns::OnBeforeMdnsDestroy() {
   need_dalay_mdns_tasks_ = true;
   weak_ptr_factory_.InvalidateWeakPtrs();
-  FOR_EACH_OBSERVER(Proxy, proxies_, OnMdnsDestroy());
+  for (Proxy& observer : proxies_)
+    observer.OnMdnsDestroy();
 }
 
 void ServiceDiscoveryClientMdns::DestroyMdns() {