Re-land: Toggle spoken feedback if two fingers are held down.

ui/chromeos/touch_exploration_controller.h

Index: ui/chromeos/touch_exploration_controller.h
diff --git a/ui/chromeos/touch_exploration_controller.h b/ui/chromeos/touch_exploration_controller.h
index 0af2d079f08478a735440c089a2f7d247dd647e3..6727c2a5eded9d6faf66f69cc16bfa2c649ddee5 100644
--- a/ui/chromeos/touch_exploration_controller.h
+++ b/ui/chromeos/touch_exploration_controller.h
@@ -25,6 +25,7 @@ namespace ui {
 class Event;
 class GestureEvent;
 class GestureProviderAura;
+class TouchAccessibilityEnabler;
 class TouchEvent;
 
 // A delegate to handle commands in response to detected accessibility gesture
@@ -180,7 +181,8 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
  public:
   explicit TouchExplorationController(
       aura::Window* root_window,
-      ui::TouchExplorationControllerDelegate* delegate);
+      ui::TouchExplorationControllerDelegate* delegate,
+      TouchAccessibilityEnabler* touch_accessibility_enabler);
   ~TouchExplorationController() override;
 
   // Make synthesized touch events are anchored at this point. This is
@@ -506,6 +508,12 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
   // LocatedEvents within this area should be left alone.
   gfx::Rect exclude_bounds_;
 
+  // Code that detects a touch-screen gesture to enable or disable
+  // accessibility. That handler is always running, whereas this is not,
+  // but events need to be sent to TouchAccessibilityEnabler before being
+  // rewritten when TouchExplorationController is running.
+  TouchAccessibilityEnabler* touch_accessibility_enabler_;
+
   DISALLOW_COPY_AND_ASSIGN(TouchExplorationController);
 };