Adjust ChromeVox (spoken feedback) strings and make it possible for announcemen

ts to occur directly in the extension.

BUG=261451
TEST=On Aura, rapidly turn ChromeVox on and off (on login/locked screen, user s
creens). Verify behaviors in above bug are true. Depends on a ChromeVox change.

Review URL: https://codereview.chromium.org/42743003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232886 0039d316-1c4b-4281-b951-d872f2087c98

chrome/app/chromeos_strings.grdp

@@ -321,7 +321,7 @@ Press any key to continue exploring.
     Accessibility
   </message>
   <message name="IDS_OOBE_SPOKEN_FEEDBACK_OPTION" desc="Spoken feedback option shown on OOBE screens accessibility menu.">
-    Spoken feedback
+    ChromeVox (spoken feedback)
   </message>
   <message name="IDS_OOBE_LARGE_CURSOR_OPTION" desc="Large mouse cursor option shown on OOBE screens accessibility menu.">
     Large mouse cursor
@@ -937,7 +937,7 @@ Press any key to continue exploring.
     Show large mouse cursor
   </message>
   <message name="IDS_OPTIONS_SETTINGS_ACCESSIBILITY_SPOKEN_FEEDBACK_DESCRIPTION" desc="In the settings tab, the text next to the checkbox for spoken feedback.">
-    Enable spoken feedback
+    Enable ChromeVox (spoken feedback)
   </message>
   <message name="IDS_OPTIONS_SETTINGS_ACCESSIBILITY_HIGH_CONTRAST_DESCRIPTION" desc="In the settings tab, the text next to the checkbox for high contrast mode.">
     Use high contrast mode
@@ -2406,10 +2406,10 @@ Press any key to continue exploring.
     Mouse
   </message>
   <message name="IDS_STATUSBAR_SPOKEN_FEEDBACK_ENABLED" desc="The tooltip for the status bar button to indicate that spoken feedback has been enabled.">
-    Spoken feedback is enabled.
+    ChromeVox (spoken feedback) is enabled. Press Ctrl+Alt+Z to disable.
   </message>
   <message name="IDS_STATUSBAR_DISABLE_SPOKEN_FEEDBACK" desc="The menu option to disable spoken feedback accessibility feature.">
-    Disable spoken feedback
+    Disable ChromeVox (spoken feedback)
   </message>
   <message name="IDS_STATUSBAR_NETWORK_DEVICE_ETHERNET" desc="The ethernet network device.">
     Ethernet
@@ -2672,12 +2672,6 @@ Battery full
   <message name="IDS_CHROMEOS_ACC_TEXT_UNSELECTED" desc="A phrase to indicate to the user that text has been unselected.">
     Unselected
   </message>
-  <message name="IDS_CHROMEOS_ACC_SPOKEN_FEEDBACK_ENABLED" desc="A phrase to speak when spoken feedback is enabled.">
-    Enabling spoken feedback.
-  </message>
-  <message name="IDS_CHROMEOS_ACC_SPOKEN_FEEDBACK_DISABLED" desc="A phrase to speak when spoken feedback is disabled.">
-    Disabling spoken feedback.
-  </message>
   <message name="IDS_CHROMEOS_ACC_USERNAME_LABEL" desc="Label for the username text field.">
     Username.
   </message>
@@ -3274,7 +3268,7 @@ Battery full
     Toggle speech input
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_TOGGLE_SPOKEN_FEEDBACK" desc="The text in the keyboard overlay to explain the shortcut (enable or disable spoken feedback).">
-    Toggle spoken feedback
+    Toggle ChromeVox (spoken feedback)
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_UNDO" desc="The text in the keyboard overlay to explain the shortcut.">
     Undo

chrome/browser/accessibility/accessibility_extension_api.cc

@@ -10,6 +10,8 @@
 #include "chrome/browser/accessibility/accessibility_extension_api_constants.h"
 #include "chrome/browser/extensions/api/tabs/tabs_constants.h"
 #include "chrome/browser/extensions/event_router.h"
+#include "chrome/browser/extensions/extension_host.h"
+#include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/extension_tab_util.h"
 #include "chrome/browser/infobars/confirm_infobar_delegate.h"
@@ -17,7 +19,9 @@
 #include "chrome/browser/infobars/infobar_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/extensions/api/experimental_accessibility.h"
+#include "chrome/common/extensions/background_info.h"
 #include "content/public/browser/browser_accessibility_state.h"
+#include "extensions/browser/lazy_background_task_queue.h"
 #include "extensions/common/error_utils.h"
 
 namespace keys = extension_accessibility_api_constants;
@@ -164,6 +168,33 @@ void ExtensionAccessibilityEventRouter::OnMenuClosed(
                 args.Pass());
 }
 
+void ExtensionAccessibilityEventRouter::OnChromeVoxLoadStateChanged(
+    Profile* profile,
+    bool loading,
+    bool make_announcements) {
+  scoped_ptr<base::ListValue> event_args(new base::ListValue());
+  event_args->Append(base::Value::CreateBooleanValue(loading));
+  event_args->Append(base::Value::CreateBooleanValue(make_announcements));
+  ExtensionAccessibilityEventRouter::DispatchEventToChromeVox(profile,
+      experimental_accessibility::OnChromeVoxLoadStateChanged::kEventName,
+      event_args.Pass());
+}
+
+// Static.
+void ExtensionAccessibilityEventRouter::DispatchEventToChromeVox(
+    Profile* profile,
+    const char* event_name,
+    scoped_ptr<base::ListValue> event_args) {
+  extensions::ExtensionSystem* system =
+      extensions::ExtensionSystem::Get(profile);
+  if (!system)
+    return;
+  scoped_ptr<extensions::Event> event(new extensions::Event(event_name,
+                                                            event_args.Pass()));
+  system->event_router()->DispatchEventToExtension(
+      extension_misc::kChromeVoxExtensionId, event.Pass());
+}
+
 void ExtensionAccessibilityEventRouter::DispatchEvent(
     Profile* profile,
     const char* event_name,

chrome/browser/accessibility/accessibility_extension_api.h

@@ -14,6 +14,10 @@
 #include "chrome/browser/extensions/chrome_extension_function.h"
 #include "ui/base/accessibility/accessibility_types.h"
 
+namespace extensions {
+class ExtensionHost;
+} // namespace extensions
+
 // Observes the profile and routes accessibility notifications as events
 // to the extension system.
 class ExtensionAccessibilityEventRouter {
@@ -54,6 +58,16 @@ class ExtensionAccessibilityEventRouter {
   void HandleControlEvent(ui::AccessibilityTypes::Event event,
                           const AccessibilityControlInfo* info);
 
+  void OnChromeVoxLoadStateChanged(
+      Profile* profile,
+      bool loading,
+      bool make_announcements);
+
+  static void DispatchEventToChromeVox(
+      Profile* profile,
+      const char* event_name,
+      scoped_ptr<base::ListValue> event_args);
+
  private:
   friend struct DefaultSingletonTraits<ExtensionAccessibilityEventRouter>;
 

chrome/browser/chromeos/accessibility/accessibility_manager.cc

@@ -32,6 +32,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/speech/tts_controller.h"
+#include "chrome/common/extensions/api/experimental_accessibility.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_messages.h"
 #include "chrome/common/extensions/manifest_handlers/content_scripts_handler.h"
@@ -287,8 +288,8 @@ AccessibilityManager::AccessibilityManager()
       high_contrast_enabled_(false),
       autoclick_delay_ms_(ash::AutoclickController::kDefaultAutoclickDelayMs),
       spoken_feedback_notification_(ash::A11Y_NOTIFICATION_NONE),
-      weak_ptr_factory_(this) {
-
+      weak_ptr_factory_(this),
+      should_speak_chrome_vox_announcements_on_user_screen_(true) {
   notification_registrar_.Add(this,
                               chrome::NOTIFICATION_LOGIN_OR_LOCK_WEBUI_VISIBLE,
                               content::NotificationService::AllSources());
@@ -409,10 +410,6 @@ void AccessibilityManager::UpdateSpokenFeedbackFromPref() {
 
   spoken_feedback_enabled_ = enabled;
 
-  Speak(l10n_util::GetStringUTF8(
-      enabled ? IDS_CHROMEOS_ACC_SPOKEN_FEEDBACK_ENABLED :
-      IDS_CHROMEOS_ACC_SPOKEN_FEEDBACK_DISABLED).c_str());
-
   ExtensionAccessibilityEventRouter::GetInstance()->
       SetAccessibilityEnabled(enabled);
 
@@ -423,10 +420,20 @@ void AccessibilityManager::UpdateSpokenFeedbackFromPref() {
       content::NotificationService::AllSources(),
       content::Details<AccessibilityStatusEventDetails>(&details));
 
-  if (enabled)
+  if (enabled) {
     LoadChromeVox();
-  else
-    UnloadChromeVox();
+    ExtensionAccessibilityEventRouter::GetInstance()->
+        OnChromeVoxLoadStateChanged(profile_,
+            true,
+            chrome_vox_loaded_on_lock_screen_ ||
+                should_speak_chrome_vox_announcements_on_user_screen_);
+
+    should_speak_chrome_vox_announcements_on_user_screen_ =
+        chrome_vox_loaded_on_lock_screen_;
+  } else {
+    ExtensionAccessibilityEventRouter::GetInstance()->
+        OnChromeVoxLoadStateChanged(profile_, false, false);
+  }
 }
 
 void AccessibilityManager::LoadChromeVox() {
@@ -686,6 +693,10 @@ void AccessibilityManager::SetProfile(Profile* profile) {
         base::Bind(
             &AccessibilityManager::UpdateChromeOSAccessibilityHistograms,
             base::Unretained(this)));
+
+    extensions::ExtensionSystem::Get(profile)->event_router()->RegisterObserver(
+        this, extensions::api::experimental_accessibility::
+            OnChromeVoxLoadStateChanged::kEventName);
   }
 
   large_cursor_pref_handler_.HandleProfileChanged(profile_, profile);
@@ -769,6 +780,9 @@ void AccessibilityManager::Observe(
     case chrome::NOTIFICATION_SESSION_STARTED:
       // Update |profile_| when entering a session.
       SetProfile(ProfileManager::GetDefaultProfile());
+
+      // Ensure ChromeVox makes announcements at the start of new sessions.
+      should_speak_chrome_vox_announcements_on_user_screen_ = true;
       break;
     case chrome::NOTIFICATION_PROFILE_DESTROYED: {
       // Update |profile_| when exiting a session or shutting down.
@@ -797,4 +811,28 @@ void AccessibilityManager::OnDisplayStateChanged(
   if (display_state.available)
     EnableSpokenFeedback(true, ash::A11Y_NOTIFICATION_SHOW);
 }
+
+void AccessibilityManager::OnListenerAdded(
+    const extensions::EventListenerInfo& details) {
+  if (details.extension_id != extension_misc::kChromeVoxExtensionId)
+    return;
+
+    ExtensionAccessibilityEventRouter::GetInstance()->
+        OnChromeVoxLoadStateChanged(profile_,
+            IsSpokenFeedbackEnabled(),
+            chrome_vox_loaded_on_lock_screen_ ||
+                should_speak_chrome_vox_announcements_on_user_screen_);
+
+    should_speak_chrome_vox_announcements_on_user_screen_ =
+        chrome_vox_loaded_on_lock_screen_;
+}
+
+void AccessibilityManager::OnListenerRemoved(
+    const extensions::EventListenerInfo& details) {
+  if (details.extension_id != extension_misc::kChromeVoxExtensionId)
+    return;
+
+  UnloadChromeVox();
+}
+
 }  // namespace chromeos

chrome/browser/chromeos/accessibility/accessibility_manager.h

@@ -10,6 +10,8 @@
 #include "base/prefs/pref_change_registrar.h"
 #include "chrome/browser/chromeos/accessibility/accessibility_util.h"
 #include "chrome/browser/extensions/api/braille_display_private/braille_controller.h"
+#include "chrome/browser/extensions/event_router.h"
+#include "chrome/browser/extensions/extension_system.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
@@ -36,6 +38,7 @@ struct AccessibilityStatusEventDetails {
 // watching profile notifications and pref-changes.
 // TODO(yoshiki): merge MagnificationManager with AccessibilityManager.
 class AccessibilityManager : public content::NotificationObserver,
+    public extensions::EventRouter::Observer,
     extensions::api::braille_display_private::BrailleObserver {
  public:
   // Creates an instance of AccessibilityManager, this should be called once,
@@ -156,6 +159,12 @@ class AccessibilityManager : public content::NotificationObserver,
       const extensions::api::braille_display_private::DisplayState&
           display_state) OVERRIDE;
 
+  // EventRouter::Observer implementation.
+  virtual void OnListenerAdded(
+      const extensions::EventListenerInfo& details) OVERRIDE;
+  virtual void OnListenerRemoved(
+      const extensions::EventListenerInfo& details) OVERRIDE;
+
   // Profile which has the current a11y context.
   Profile* profile_;
 
@@ -185,6 +194,8 @@ class AccessibilityManager : public content::NotificationObserver,
 
   base::WeakPtrFactory<AccessibilityManager> weak_ptr_factory_;
 
+  bool should_speak_chrome_vox_announcements_on_user_screen_;
+
   DISALLOW_COPY_AND_ASSIGN(AccessibilityManager);
 };
 

chrome/common/extensions/api/experimental_accessibility.json

@@ -293,6 +293,23 @@
             "description": "Information about the menu that was closed."
           }
         ]
+      },
+      {
+        "name": "onChromeVoxLoadStateChanged",
+        "type": "function",
+        "description": "Fired ChromeVox load state changes.",
+        "parameters": [
+          {
+            "type": "boolean",
+            "name": "loading",
+            "description": "True if ChromeVox is loading; false if ChromeVox is unloading."
+          },
+          {
+            "type": "boolean",
+            "name": "makeAnnouncements",
+            "description": "Whether to make introductory announcements."
+          }
+        ]
       }
     ]
   }