Implement touch exploration touch typing

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 6727c2a5eded9d6faf66f69cc16bfa2c649ddee5..4076433f7c316ac148ad8ec7513b9a3b7a699f27 100644
--- a/ui/chromeos/touch_exploration_controller.h
+++ b/ui/chromeos/touch_exploration_controller.h
@@ -194,6 +194,10 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
   // |bounds| are in root window coordinates.
   void SetExcludeBounds(const gfx::Rect& bounds);
 
+  // Updates |lift_activation_bounds_|. See |lift_activation_bounds_| for more
+  // information.
+  void SetLiftActivationBounds(const gfx::Rect& bounds);
+
  private:
   friend class TouchExplorationControllerTestApi;
 
@@ -296,7 +300,16 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
 
   void PlaySoundForTimer();
 
-  void SendSimulatedClick();
+  // Sends a simulated click, if an anchor point was set explicitly. Otherwise,
+  // sends a simulated tap at anchor point.
+  void SendSimulatedClickOrTap();
+
+  // Sends a simulated tap at anchor point.
+  void SendSimulatedTap();
+
+  // Sends a simulated tap, if the anchor point falls within lift activation
+  // bounds.
+  void MaybeSendSimulatedTapInLiftActivationBounds(const ui::TouchEvent& event);
 
   // Some constants used in touch_exploration_controller:
 
@@ -514,6 +527,11 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
   // rewritten when TouchExplorationController is running.
   TouchAccessibilityEnabler* touch_accessibility_enabler_;
 
+  // Any touch exploration that both starts and ends (touch pressed, and
+  // released) within this rectangle, triggers a simulated single finger tap at
+  // the anchor point on release.
+  gfx::Rect lift_activation_bounds_;
+
   DISALLOW_COPY_AND_ASSIGN(TouchExplorationController);
 };