Remove usage of FOR_EACH_OBSERVER macro in headless domain_cc.template

headless/lib/browser/domain_cc.template

 // This file is generated
 
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "headless/public/domains/{{domain.domain | camelcase_to_hacker_style}}.h"
 
 #include "base/bind.h"
 
@@ skipping 84 matching lines @@
 }
 {% endfor %}
 {% if "events" in domain %}
   {% for event in domain.events %}
 
 {# Generate dispatchers which call registered observers for an event. #}
 void Domain::Dispatch{{event.name | to_title_case}}Event(const base::Value& params) {
   ErrorReporter errors;
   std::unique_ptr<{{event.name | to_title_case}}Params> parsed_params({{event.name | to_title_case}}Params::Parse(params, &errors));
   DCHECK(!errors.HasErrors());
-  FOR_EACH_OBSERVER(ExperimentalObserver, observers_, On{{event.name | to_title_case}}(*parsed_params));
+  for (ExperimentalObserver& observer : observers_) {
+    observer.On{{event.name | to_title_case}}(*parsed_params);
+  }
 }
   {% endfor %}
 {% endif %}
 
 Domain::Domain(internal::MessageDispatcher* dispatcher)
     : dispatcher_(dispatcher) {
   {% if "events" in domain %}
     {# Register all events in this domain. #}
     {% for event in domain.events %}
   dispatcher_->RegisterEventHandler(
@@ skipping 17 matching lines @@
 }
 
 void ExperimentalDomain::RemoveObserver(ExperimentalObserver* observer) {
   observers_.RemoveObserver(observer);
 }
   {% endif %}
 
 }  // namespace {{domain.domain | camelcase_to_hacker_style}}
 
 } // namespace headless