[Android] Always insert a TouchCancel if window or tab focus is lost

ui/events/gesture_detection/gesture_provider.h

Index: ui/events/gesture_detection/gesture_provider.h
diff --git a/ui/events/gesture_detection/gesture_provider.h b/ui/events/gesture_detection/gesture_provider.h
index ad2c106b9753b3f30c006daea61b98ad144f913e..d8542194ccecf19864e1a337354629a2826a9816 100644
--- a/ui/events/gesture_detection/gesture_provider.h
+++ b/ui/events/gesture_detection/gesture_provider.h
@@ -45,12 +45,6 @@ class GESTURE_DETECTION_EXPORT GestureProvider {
   // Resets all gesture detectors; called on DidStartLoading().
   void ResetGestureDetectors();
 
-  // Cancel the current touch event sequence by sending ACTION_CANCEL, and
-  // ignore all the subsequent events until the next ACTION_DOWN.
-  // One example usecase is to stop processing the touch events when showing
-  // a context popup menu.
-  void CancelActiveTouchSequence();
-
   // Update whether multi-touch gestures are supported.
   void SetMultiTouchSupportEnabled(bool enabled);
 
@@ -79,6 +73,11 @@ class GESTURE_DETECTION_EXPORT GestureProvider {
   // whether double-tap is supported), see |Config.disable_click_delay|.
   bool IsClickDelayDisabled() const;
 
+  // May be NULL if there is no currently active touch sequence.
+  const ui::MotionEvent* current_down_event() const {
+    return current_down_event_.get();
+  }
+
  private:
   void InitGestureDetectors(const Config& config);