Support multiple Observer instances for ArcSupportHost.

chrome/browser/chromeos/arc/arc_support_host.cc

 // 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 "chrome/browser/chromeos/arc/arc_support_host.h"
 
 #include <string>
+#include <utility>
 
 #include "ash/common/system/chromeos/devicetype_utils.h"
 #include "base/i18n/timezone.h"
 #include "base/json/json_reader.h"
 #include "base/json/json_writer.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/extension_util.h"
@@ skipping 122 matching lines @@
 const char ArcSupportHost::kStorageId[] = "arc_support";
 
 ArcSupportHost::ArcSupportHost(Profile* profile) : profile_(profile) {}
 
 ArcSupportHost::~ArcSupportHost() {
   if (message_host_)
     DisconnectMessageHost();
 }
 
 void ArcSupportHost::AddObserver(Observer* observer) {
-  DCHECK(!observer_);
-  observer_ = observer;
+  observer_list_.AddObserver(observer);
+}
+
+void ArcSupportHost::RemoveObserver(Observer* observer) {
+  observer_list_.RemoveObserver(observer);
+}
+
+bool ArcSupportHost::HasObserver(Observer* observer) {
+  return observer_list_.HasObserver(observer);
 }
 
 void ArcSupportHost::SetArcManaged(bool is_arc_managed) {
   DCHECK(!message_host_);
   is_arc_managed_ = is_arc_managed;
 }
 
 void ArcSupportHost::Close() {
   ui_page_ = UIPage::NO_PAGE;
   if (!message_host_) {
@@ skipping 314 matching lines @@
   message_host_->SendMessage(message);
 }
 
 void ArcSupportHost::OnMessage(const base::DictionaryValue& message) {
   std::string event;
   if (!message.GetString(kEvent, &event)) {
     NOTREACHED();
     return;
   }
 
-  if (!observer_) {
-    LOG(ERROR) << "No observer is found.";
-    return;
-  }
-
   if (event == kEventOnWindowClosed) {
-    observer_->OnWindowClosed();
+    for (auto& observer : observer_list_)
+      observer.OnWindowClosed();
   } else if (event == kEventOnAuthSucceeded) {
     std::string code;
     if (message.GetString(kCode, &code)) {
-      observer_->OnAuthSucceeded(code);
+      for (auto& observer : observer_list_)
+        observer.OnAuthSucceeded(code);
     } else {
       NOTREACHED();
     }
   } else if (event == kEventOnAgreed) {
     bool is_metrics_enabled;
     bool is_backup_restore_enabled;
     bool is_location_service_enabled;
     if (message.GetBoolean(kIsMetricsEnabled, &is_metrics_enabled) &&
         message.GetBoolean(kIsBackupRestoreEnabled,
                            &is_backup_restore_enabled) &&
         message.GetBoolean(kIsLocationServiceEnabled,
                            &is_location_service_enabled)) {
-      observer_->OnTermsAgreed(is_metrics_enabled, is_backup_restore_enabled,
+      for (auto& observer : observer_list_) {
+        observer.OnTermsAgreed(is_metrics_enabled, is_backup_restore_enabled,
                                is_location_service_enabled);
+      }
     } else {
       NOTREACHED();
     }
   } else if (event == kEventOnRetryClicked) {
-    observer_->OnRetryClicked();
+    for (auto& observer : observer_list_)
+      observer.OnRetryClicked();
   } else if (event == kEventOnSendFeedbackClicked) {
-    observer_->OnSendFeedbackClicked();
+    for (auto& observer : observer_list_)
+      observer.OnSendFeedbackClicked();
   } else {
     LOG(ERROR) << "Unknown message: " << event;
     NOTREACHED();
   }
 }