Separate motion event touch geometry orientation from stylus orientation.

ui/events/gesture_detection/motion_event_generic.h

Index: ui/events/gesture_detection/motion_event_generic.h
diff --git a/ui/events/gesture_detection/motion_event_generic.h b/ui/events/gesture_detection/motion_event_generic.h
index 635734208bdbd258e2eb784b5785f9ed8d2ded3e..175a9b8ab0428725a3c0167e0f8d765f55b0f6c1 100644
--- a/ui/events/gesture_detection/motion_event_generic.h
+++ b/ui/events/gesture_detection/motion_event_generic.h
@@ -27,7 +27,7 @@ struct GESTURE_DETECTION_EXPORT PointerProperties {
   float pressure;
   float touch_major;
   float touch_minor;
-  float orientation;
+  float touch_orientation;
   // source_device_id is only used on Aura.
   int source_device_id;
 };
@@ -54,7 +54,7 @@ class GESTURE_DETECTION_EXPORT MotionEventGeneric : public MotionEvent {
   float GetRawY(size_t pointer_index) const override;
   float GetTouchMajor(size_t pointer_index) const override;
   float GetTouchMinor(size_t pointer_index) const override;
-  float GetOrientation(size_t pointer_index) const override;
+  float GetTouchOrientation(size_t pointer_index) const override;
   float GetPressure(size_t pointer_index) const override;
   ToolType GetToolType(size_t pointer_index) const override;
   int GetButtonState() const override;