Introduce AccessibiltyDelegate

I'll incorporate changes in https://codereview.chromium.org/27238008 when it's landed.

BUG=none

Review URL: https://codereview.chromium.org/37663004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230619 0039d316-1c4b-4281-b951-d872f2087c98

ash/accelerators/accelerator_controller.cc

@@ -134,8 +134,10 @@ void HandleCycleLinear(const ui::Accelerator& accelerator) {
 }
 
 bool HandleAccessibleFocusCycle(bool reverse) {
-  if (!Shell::GetInstance()->delegate()->IsSpokenFeedbackEnabled())
+  if (!Shell::GetInstance()->accessibility_delegate()->
+      IsSpokenFeedbackEnabled()) {
     return false;
+  }
   aura::Window* active_window = ash::wm::GetActiveWindow();
   if (!active_window)
     return false;
@@ -157,10 +159,11 @@ bool HandleAccessibleFocusCycle(bool reverse) {
 }
 
 void HandleSilenceSpokenFeedback() {
-  if (!Shell::GetInstance()->delegate()->IsSpokenFeedbackEnabled())
+  AccessibilityDelegate* delegate =
+      Shell::GetInstance()->accessibility_delegate();
+  if (!delegate->IsSpokenFeedbackEnabled())
     return;
-
-  Shell::GetInstance()->delegate()->SilenceSpokenFeedback();
+  delegate->SilenceSpokenFeedback();
 }
 
 #if defined(OS_CHROMEOS)
@@ -180,7 +183,7 @@ bool HandleCrosh() {
 }
 
 bool HandleToggleSpokenFeedback() {
-  Shell::GetInstance()->delegate()->
+  Shell::GetInstance()->accessibility_delegate()->
       ToggleSpokenFeedback(A11Y_NOTIFICATION_SHOW);
   return true;
 }
@@ -662,7 +665,8 @@ bool AcceleratorController::PerformAction(int action,
       // consume the key since Search+Shift is one of the shortcuts the a11y
       // feature uses. crbug.com/132296
       DCHECK_EQ(ui::VKEY_LWIN, accelerator.key_code());
-      if (Shell::GetInstance()->delegate()->IsSpokenFeedbackEnabled())
+      if (Shell::GetInstance()->accessibility_delegate()->
+          IsSpokenFeedbackEnabled())
         return false;
       ash::Shell::GetInstance()->ToggleAppList(NULL);
       return true;

ash/accelerators/accelerator_controller_unittest.cc

@@ -4,6 +4,7 @@
 
 #include "ash/accelerators/accelerator_controller.h"
 #include "ash/accelerators/accelerator_table.h"
+#include "ash/accessibility_delegate.h"
 #include "ash/caps_lock_delegate.h"
 #include "ash/display/display_manager.h"
 #include "ash/ime_control_delegate.h"
@@ -957,9 +958,8 @@ TEST_F(AcceleratorControllerTest, GlobalAccelerators) {
 }
 
 TEST_F(AcceleratorControllerTest, GlobalAcceleratorsToggleAppList) {
-  test::TestShellDelegate* delegate =
-      reinterpret_cast<test::TestShellDelegate*>(
-          ash::Shell::GetInstance()->delegate());
+  AccessibilityDelegate* delegate =
+          ash::Shell::GetInstance()->accessibility_delegate();
   EXPECT_FALSE(ash::Shell::GetInstance()->GetAppListTargetVisibility());
 
   // The press event should not open the AppList, the release should instead.

ash/accessibility_delegate.h

@@ -0,0 +1,78 @@
+// Copyright 2013 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.
+
+#ifndef ASH_ACCESSIBILITY_DELEGATE_H_
+#define ASH_ACCESSIBILITY_DELEGATE_H_
+
+#include "ash/ash_export.h"
+#include "ash/magnifier/magnifier_constants.h"
+
+namespace ash {
+
+enum AccessibilityNotificationVisibility {
+  A11Y_NOTIFICATION_NONE,
+  A11Y_NOTIFICATION_SHOW,
+};
+
+// A deletate class to control accessibility features.
+class ASH_EXPORT AccessibilityDelegate {
+ public:
+  AccessibilityDelegate() {}
+  virtual ~AccessibilityDelegate() {}
+
+  // Invoked to toggle spoken feedback for accessibility
+  virtual void ToggleSpokenFeedback(
+      AccessibilityNotificationVisibility notify) = 0;
+
+  // Returns true if spoken feedback is enabled.
+  virtual bool IsSpokenFeedbackEnabled() const = 0;
+
+  // Invoked to toggle high contrast mode for accessibility.
+  virtual void ToggleHighContrast() = 0;
+
+  // Returns true if high contrast mode is enabled.
+  virtual bool IsHighContrastEnabled() const = 0;
+
+  // Invoked to enable the screen magnifier.
+  virtual void SetMagnifierEnabled(bool enabled) = 0;
+
+  // Invoked to change the type of the screen magnifier.
+  virtual void SetMagnifierType(MagnifierType type) = 0;
+
+  // Returns true if the screen magnifier is enabled or not.
+  virtual bool IsMagnifierEnabled() const = 0;
+
+  // Returns the current screen magnifier mode.
+  virtual MagnifierType GetMagnifierType() const = 0;
+
+  // Invoked to enable Large Cursor.
+  virtual void SetLargeCursorEnabled(bool enabled) = 0;
+
+  // Returns ture if Large Cursor is enabled or not.
+  virtual bool IsLargeCursorEnabled() const = 0;
+
+  // Invoked to enable autoclick.
+  virtual void SetAutoclickEnabled(bool enabled) = 0;
+
+  // Returns if autoclick is enabled or not.
+  virtual bool IsAutoclickEnabled() const = 0;
+
+  // Returns true if the user wants to show accesibility menu even when all the
+  // accessibility features are disabled.
+  virtual bool ShouldAlwaysShowAccessibilityMenu() const = 0;
+
+  // Cancel all current and queued speech immediately.
+  virtual void SilenceSpokenFeedback() const = 0;
+
+  // Saves the zoom scale of the full screen magnifier.
+  virtual void SaveScreenMagnifierScale(double scale) = 0;
+
+  // Gets a saved value of the zoom scale of full screen magnifier. If a value
+  // is not saved, return a negative value.
+  virtual double GetSavedScreenMagnifierScale() = 0;
+};
+
+}  // namespace ash
+
+#endif  // ASH_ACCESSIBILITYDELEGATE_H_

ash/ash.gyp

@@ -67,6 +67,7 @@
         'accelerators/focus_manager_factory.h',
         'accelerators/nested_dispatcher_controller.cc',
         'accelerators/nested_dispatcher_controller.h',
+        'accessibility_delegate.h',
         'autoclick/autoclick_controller.cc',
         'autoclick/autoclick_controller.h',
         'ash_constants.cc',
@@ -80,6 +81,8 @@
         'caps_lock_delegate_stub.h',
         'debug.cc',
         'debug.h',
+        'default_accessibility_delegate.cc',
+        'default_accessibility_delegate.h',
         'default_user_wallpaper_delegate.cc',
         'default_user_wallpaper_delegate.h',
         'desktop_background/desktop_background_controller.cc',

ash/default_accessibility_delegate.cc

@@ -0,0 +1,87 @@
+// Copyright 2013 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 "ash/default_accessibility_delegate.h"
+
+#include <limits>
+
+namespace ash {
+namespace internal {
+
+DefaultAccessibilityDelegate::DefaultAccessibilityDelegate()
+    : spoken_feedback_enabled_(false),
+      high_contrast_enabled_(false),
+      screen_magnifier_enabled_(false),
+      screen_magnifier_type_(kDefaultMagnifierType),
+      large_cursor_enabled_(false),
+      autoclick_enabled_(false) {
+}
+
+DefaultAccessibilityDelegate::~DefaultAccessibilityDelegate() {}
+
+bool DefaultAccessibilityDelegate::IsSpokenFeedbackEnabled() const {
+  return spoken_feedback_enabled_;
+}
+
+void DefaultAccessibilityDelegate::ToggleHighContrast() {
+  high_contrast_enabled_ = !high_contrast_enabled_;
+}
+
+bool DefaultAccessibilityDelegate::IsHighContrastEnabled() const {
+  return high_contrast_enabled_;
+}
+
+void DefaultAccessibilityDelegate::SetMagnifierEnabled(bool enabled) {
+  screen_magnifier_enabled_ = enabled;
+}
+
+void DefaultAccessibilityDelegate::SetMagnifierType(MagnifierType type) {
+  screen_magnifier_type_ = type;
+}
+
+bool DefaultAccessibilityDelegate::IsMagnifierEnabled() const {
+  return screen_magnifier_enabled_;
+}
+
+MagnifierType DefaultAccessibilityDelegate::GetMagnifierType() const {
+  return screen_magnifier_type_;
+}
+
+void DefaultAccessibilityDelegate::SetLargeCursorEnabled(bool enabled) {
+  large_cursor_enabled_ = enabled;
+}
+
+bool DefaultAccessibilityDelegate::IsLargeCursorEnabled() const {
+  return large_cursor_enabled_;
+}
+
+void DefaultAccessibilityDelegate::SetAutoclickEnabled(bool enabled) {
+  autoclick_enabled_ = enabled;
+}
+
+bool DefaultAccessibilityDelegate::IsAutoclickEnabled() const {
+  return autoclick_enabled_;
+}
+
+bool DefaultAccessibilityDelegate::ShouldAlwaysShowAccessibilityMenu() const {
+  return false;
+}
+
+void DefaultAccessibilityDelegate::SilenceSpokenFeedback() const {
+}
+
+void DefaultAccessibilityDelegate::ToggleSpokenFeedback(
+    AccessibilityNotificationVisibility notify) {
+  spoken_feedback_enabled_ = !spoken_feedback_enabled_;
+}
+
+void DefaultAccessibilityDelegate::SaveScreenMagnifierScale(double scale) {
+}
+
+double DefaultAccessibilityDelegate::GetSavedScreenMagnifierScale() {
+  return std::numeric_limits<double>::min();
+}
+
+}  // namespace internal
+}  // namespace ash

ash/default_accessibility_delegate.h

@@ -0,0 +1,53 @@
+// Copyright 2013 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.
+
+#ifndef ASH_DEFAULT_ACCESSIBILITY_DELEGATE_H_
+#define ASH_DEFAULT_ACCESSIBILITY_DELEGATE_H_
+
+#include "ash/accessibility_delegate.h"
+#include "ash/ash_export.h"
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+
+namespace ash {
+namespace internal {
+
+class ASH_EXPORT DefaultAccessibilityDelegate : public AccessibilityDelegate {
+ public:
+  DefaultAccessibilityDelegate();
+  virtual ~DefaultAccessibilityDelegate();
+
+  virtual bool IsSpokenFeedbackEnabled() const OVERRIDE;
+  virtual void ToggleHighContrast() OVERRIDE;
+  virtual bool IsHighContrastEnabled() const OVERRIDE;
+  virtual void SetMagnifierEnabled(bool enabled) OVERRIDE;
+  virtual void SetMagnifierType(MagnifierType type) OVERRIDE;
+  virtual bool IsMagnifierEnabled() const OVERRIDE;
+  virtual MagnifierType GetMagnifierType() const OVERRIDE;
+  virtual void SetLargeCursorEnabled(bool enabled) OVERRIDE;
+  virtual bool IsLargeCursorEnabled() const OVERRIDE;
+  virtual void SetAutoclickEnabled(bool enabled) OVERRIDE;
+  virtual bool IsAutoclickEnabled() const OVERRIDE;
+  virtual bool ShouldAlwaysShowAccessibilityMenu() const OVERRIDE;
+  virtual void SilenceSpokenFeedback() const OVERRIDE;
+  virtual void ToggleSpokenFeedback(
+      AccessibilityNotificationVisibility notify) OVERRIDE;
+  virtual void SaveScreenMagnifierScale(double scale) OVERRIDE;
+  virtual double GetSavedScreenMagnifierScale() OVERRIDE;
+
+ private:
+  bool spoken_feedback_enabled_;
+  bool high_contrast_enabled_;
+  bool screen_magnifier_enabled_;
+  MagnifierType screen_magnifier_type_;
+  bool large_cursor_enabled_;
+  bool autoclick_enabled_;
+
+  DISALLOW_COPY_AND_ASSIGN(DefaultAccessibilityDelegate);
+};
+
+}  // namespace internal
+}  // namespace ash
+
+#endif  // DEFAULT_ACCESSIBILITY_DELEGATE_H_

ash/magnifier/magnification_controller.cc

@@ -4,9 +4,9 @@
 
 #include "ash/magnifier/magnification_controller.h"
 
+#include "ash/accessibility_delegate.h"
 #include "ash/display/root_window_transformers.h"
 #include "ash/shell.h"
-#include "ash/shell_delegate.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "base/synchronization/waitable_event.h"
 #include "ui/aura/client/cursor_client.h"
@@ -503,7 +503,8 @@ void MagnificationControllerImpl::SetScale(float scale, bool animate) {
     return;
 
   ValidateScale(&scale);
-  ash::Shell::GetInstance()->delegate()->SaveScreenMagnifierScale(scale);
+  ash::Shell::GetInstance()->accessibility_delegate()->
+      SaveScreenMagnifierScale(scale);
   RedrawKeepingMousePosition(scale, animate);
 }
 
@@ -543,7 +544,8 @@ void MagnificationControllerImpl::EnsurePointIsVisible(
 void MagnificationControllerImpl::SetEnabled(bool enabled) {
   if (enabled) {
     float scale =
-        ash::Shell::GetInstance()->delegate()->GetSavedScreenMagnifierScale();
+        ash::Shell::GetInstance()->accessibility_delegate()->
+        GetSavedScreenMagnifierScale();
     if (scale <= 0.0f)
       scale = kInitialMagnifiedScale;
     ValidateScale(&scale);
@@ -554,7 +556,8 @@ void MagnificationControllerImpl::SetEnabled(bool enabled) {
 
     is_enabled_ = enabled;
     RedrawKeepingMousePosition(scale, true);
-    ash::Shell::GetInstance()->delegate()->SaveScreenMagnifierScale(scale);
+    ash::Shell::GetInstance()->accessibility_delegate()->
+        SaveScreenMagnifierScale(scale);
   } else {
     // Do nothing, if already disabled.
     if (!is_enabled_)

ash/shell.cc

@@ -660,6 +660,7 @@ Shell::~Shell() {
   screen_position_controller_.reset();
 
   keyboard_controller_.reset();
+  accessibility_delegate_.reset();
 
 #if defined(OS_CHROMEOS) && defined(USE_X11)
    if (display_change_observer_)
@@ -831,6 +832,7 @@ void Shell::Init() {
   caps_lock_delegate_.reset(delegate_->CreateCapsLockDelegate());
 
   session_state_delegate_.reset(delegate_->CreateSessionStateDelegate());
+  accessibility_delegate_.reset(delegate_->CreateAccessibilityDelegate());
 
   if (!command_line->HasSwitch(views::corewm::switches::kNoDropShadows)) {
     resize_shadow_controller_.reset(new internal::ResizeShadowController());

ash/shell.h

@@ -76,6 +76,7 @@ class WindowModalityController;
 namespace ash {
 
 class AcceleratorController;
+class AccessibilityDelegate;
 class AshNativeCursorManager;
 class AutoclickController;
 class CapsLockDelegate;
@@ -366,6 +367,10 @@ class ASH_EXPORT Shell
     return session_state_delegate_.get();
   }
 
+  AccessibilityDelegate* accessibility_delegate() {
+    return accessibility_delegate_.get();
+  }
+
   HighContrastController* high_contrast_controller() {
     return high_contrast_controller_.get();
   }
@@ -573,6 +578,7 @@ class ASH_EXPORT Shell
   scoped_ptr<UserWallpaperDelegate> user_wallpaper_delegate_;
   scoped_ptr<CapsLockDelegate> caps_lock_delegate_;
   scoped_ptr<SessionStateDelegate> session_state_delegate_;
+  scoped_ptr<AccessibilityDelegate> accessibility_delegate_;
   scoped_ptr<LauncherDelegate> launcher_delegate_;
   scoped_ptr<LauncherItemDelegateManager> launcher_item_delegate_manager_;