MD Settings: Convert C++ handlers to be JavaScript-lifecycle aware.

chrome/browser/ui/webui/settings/settings_manage_profile_handler.cc

 // Copyright 2015 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/settings_manage_profile_handler.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
@@ skipping 51 matching lines @@
   web_ui()->RegisterMessageCallback(
       "addProfileShortcut",
       base::Bind(&ManageProfileHandler::HandleAddProfileShortcut,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback(
       "removeProfileShortcut",
       base::Bind(&ManageProfileHandler::HandleRemoveProfileShortcut,
                  base::Unretained(this)));
 }
 
+void ManageProfileHandler::OnJavascriptAllowed() {
+  observer_.Add(
+      &g_browser_process->profile_manager()->GetProfileAttributesStorage());
+}
+
+void ManageProfileHandler::OnJavascriptDisallowed() {
+  observer_.RemoveAll();
+}
+
 void ManageProfileHandler::OnProfileAvatarChanged(
     const base::FilePath& profile_path) {
   // This is necessary to send the potentially updated GAIA photo.
-  web_ui()->CallJavascriptFunction("cr.webUIListenerCallback",
-                                   base::StringValue("available-icons-changed"),
-                                   *GetAvailableIcons());
+  CallJavascriptFunction("cr.webUIListenerCallback",
+                         base::StringValue("available-icons-changed"),
+                         *GetAvailableIcons());
 }
 
 void ManageProfileHandler::HandleGetAvailableIcons(
     const base::ListValue* args) {
-  // This is also used as a signal that the page has loaded and is ready to
-  // observe profile avatar changes.
-  if (!observer_.IsObservingSources()) {
-    observer_.Add(
-        &g_browser_process->profile_manager()->GetProfileAttributesStorage());
-  }
+  AllowJavascript();
 
   profiles::UpdateGaiaProfileInfoIfNeeded(profile_);
 
   CHECK_EQ(1U, args->GetSize());
   const base::Value* callback_id;
   CHECK(args->Get(0, &callback_id));
   ResolveJavascriptCallback(*callback_id, *GetAvailableIcons());
 }
 
 std::unique_ptr<base::ListValue> ManageProfileHandler::GetAvailableIcons() {
@@ skipping 88 matching lines @@
   shortcut_manager->HasProfileShortcuts(
       profile_->GetPath(),
       base::Bind(&ManageProfileHandler::OnHasProfileShortcuts,
                  weak_factory_.GetWeakPtr()));
 }
 
 void ManageProfileHandler::OnHasProfileShortcuts(bool has_shortcuts) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
   const base::FundamentalValue has_shortcuts_value(has_shortcuts);
-  web_ui()->CallJavascriptFunction(
-      "settings.SyncPrivateApi.receiveHasProfileShortcuts",
-      has_shortcuts_value);
+  CallJavascriptFunction("settings.SyncPrivateApi.receiveHasProfileShortcuts",
+                         has_shortcuts_value);
 }
 
 void ManageProfileHandler::HandleAddProfileShortcut(
     const base::ListValue* args) {
   DCHECK(ProfileShortcutManager::IsFeatureEnabled());
   ProfileShortcutManager* shortcut_manager =
       g_browser_process->profile_manager()->profile_shortcut_manager();
   DCHECK(shortcut_manager);
 
   shortcut_manager->CreateProfileShortcut(profile_->GetPath());
 
   // Update the UI buttons.
   OnHasProfileShortcuts(true);
 }
 
 void ManageProfileHandler::HandleRemoveProfileShortcut(
     const base::ListValue* args) {
   DCHECK(ProfileShortcutManager::IsFeatureEnabled());
   ProfileShortcutManager* shortcut_manager =
     g_browser_process->profile_manager()->profile_shortcut_manager();
   DCHECK(shortcut_manager);
 
   shortcut_manager->RemoveProfileShortcuts(profile_->GetPath());
 
   // Update the UI buttons.
   OnHasProfileShortcuts(false);
 }
 
 }  // namespace settings