WebUI: Add JavaScript lifecycle-control to WebUIMessageHandler.

chrome/browser/ui/webui/settings/profile_info_handler.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/ui/webui/settings/profile_info_handler.h"
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 13 matching lines @@
 #include "chrome/browser/profiles/profile_avatar_icon_util.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #endif
 
 namespace settings {
 
 // static
 const char ProfileInfoHandler::kProfileInfoChangedEventName[] =
     "profile-info-changed";
 
-ProfileInfoHandler::ProfileInfoHandler(Profile* profile)
-    : profile_(profile), observers_registered_(false) {}
+ProfileInfoHandler::ProfileInfoHandler(Profile* profile) : profile_(profile) {}
 
 void ProfileInfoHandler::RegisterMessages() {
   web_ui()->RegisterMessageCallback(
       "getProfileInfo", base::Bind(&ProfileInfoHandler::HandleGetProfileInfo,
                                    base::Unretained(this)));
 }
 
-void ProfileInfoHandler::RenderViewReused() {
-  if (!observers_registered_)
-    return;
+void ProfileInfoHandler::OnJavascriptAllowed() {
+  g_browser_process->profile_manager()
+      ->GetProfileAttributesStorage()
+      .AddObserver(this);
 
+#if defined(OS_CHROMEOS)
+  registrar_.Add(this, chrome::NOTIFICATION_LOGIN_USER_IMAGE_CHANGED,
+                 content::NotificationService::AllSources());
+#endif
+}
+
+void ProfileInfoHandler::OnJavascriptDisallowed() {
   g_browser_process->profile_manager()
       ->GetProfileAttributesStorage()
       .RemoveObserver(this);
 
 #if defined(OS_CHROMEOS)
   registrar_.RemoveAll();
 #endif
-
-  observers_registered_ = false;
 }
 
 #if defined(OS_CHROMEOS)
 void ProfileInfoHandler::Observe(int type,
                                  const content::NotificationSource& source,
                                  const content::NotificationDetails& details) {
   switch (type) {
     case chrome::NOTIFICATION_LOGIN_USER_IMAGE_CHANGED:
       PushProfileInfo();
       break;
     default:
       NOTREACHED();
   }
 }
 #endif
 
 void ProfileInfoHandler::OnProfileNameChanged(
     const base::FilePath& /* profile_path */,
     const base::string16& /* old_profile_name */) {
   PushProfileInfo();
 }
 
 void ProfileInfoHandler::OnProfileAvatarChanged(
     const base::FilePath& /* profile_path */) {
   PushProfileInfo();
 }
 
 void ProfileInfoHandler::HandleGetProfileInfo(const base::ListValue* args) {
-  if (!observers_registered_) {
-    observers_registered_ = true;
-
-    g_browser_process->profile_manager()
-        ->GetProfileAttributesStorage()
-        .AddObserver(this);
-
-#if defined(OS_CHROMEOS)
-    registrar_.Add(this, chrome::NOTIFICATION_LOGIN_USER_IMAGE_CHANGED,
-                   content::NotificationService::AllSources());
-#endif
-  }
+  AllowJavascript();
 
   CHECK_EQ(1U, args->GetSize());
   const base::Value* callback_id;
   CHECK(args->Get(0, &callback_id));
 
   ResolveJavascriptCallback(*callback_id, *GetAccountNameAndIcon());
 }
 
 void ProfileInfoHandler::PushProfileInfo() {
   web_ui()->CallJavascriptFunction(
@@ skipping 41 matching lines @@
   }
 #endif  // defined(OS_CHROMEOS)
 
   base::DictionaryValue* response = new base::DictionaryValue();
   response->SetString("name", name);
   response->SetString("iconUrl", icon_url);
   return base::WrapUnique(response);
 }
 
 }  // namespace settings