Unregister access notifications when accessibility is turned off

chrome/browser/chromeos/login/wizard_accessibility_helper.cc

 // Copyright (c) 2010 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/login/wizard_accessibility_helper.h"
 
 #include "base/logging.h"
 #include "base/stl_util-inl.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/extension_accessibility_api.h"
@@ skipping 100 matching lines @@
       }
     }
   }
 }
 
 void WizardAccessibilityHelper::ToggleAccessibility(views::View* view_tree) {
   if (!IsAccessibilityEnabled()) {
     EnableAccessibilityForView(view_tree);
   } else {
     SetAccessibilityEnabled(false);
+    if (registered_notifications_)
+      UnregisterNotifications();
   }
 }
 
 void WizardAccessibilityHelper::SetAccessibilityEnabled(bool enabled) {
+  bool doSpeak = (IsAccessibilityEnabled() != enabled);
   if (g_browser_process) {
     PrefService* prefService = g_browser_process->local_state();
     prefService->SetBoolean(prefs::kAccessibilityEnabled, enabled);
     prefService->ScheduleSavePersistentPrefs();
   }
   ExtensionAccessibilityEventRouter::GetInstance()->
       SetAccessibilityEnabled(enabled);
-  accessibility_handler_->Speak(enabled ?
-      l10n_util::GetStringUTF8(IDS_CHROMEOS_ACC_ACCESS_ENABLED).c_str() :
-      l10n_util::GetStringUTF8(IDS_CHROMEOS_ACC_ACCESS_DISABLED).c_str(),
-      false, true);
+  if (doSpeak) {
+    accessibility_handler_->Speak(enabled ?
+        l10n_util::GetStringUTF8(IDS_CHROMEOS_ACC_ACCESS_ENABLED).c_str() :
+        l10n_util::GetStringUTF8(IDS_CHROMEOS_ACC_ACCESS_DISABLED).c_str(),
+        false, true);
+  }
 }
 
 void WizardAccessibilityHelper::AddViewToBuffer(views::View* view_tree) {
   if (!view_tree->GetWidget())
     return;
   bool view_exists = false;
   // Check if the view is already queued for enabling accessibility.
   // Prevent adding the same view in the buffer twice.
   for (std::map<views::View*, bool>::iterator iter = views_buffer_.begin();
       iter != views_buffer_.end(); ++iter) {
     if ((*iter).first == view_tree) {
       view_exists = true;
       break;
     }
   }
   if (!view_exists)
     views_buffer_[view_tree] = false;
 }
 
 }  // namespace chromeos