Added experimental Touch.tilt, Touch.tiltDirection support for Android

ui/events/gesture_detection/motion_event_generic.h

 // Copyright 2014 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 UI_EVENTS_GESTURE_DETECTION_UI_MOTION_EVENT_GENERIC_H_
 #define UI_EVENTS_GESTURE_DETECTION_UI_MOTION_EVENT_GENERIC_H_
 
 #include "base/basictypes.h"
 #include "base/containers/stack_container.h"
 #include "base/memory/scoped_vector.h"
@@ skipping 10 matching lines @@
   int id;
   MotionEvent::ToolType tool_type;
   float x;
   float y;
   float raw_x;
   float raw_y;
   float pressure;
   float touch_major;
   float touch_minor;
   float orientation;
+  float tilt;
   // source_device_id is only used on Aura.
   int source_device_id;
 };
 
 // A generic MotionEvent implementation.
 class GESTURE_DETECTION_EXPORT MotionEventGeneric : public MotionEvent {
  public:
   MotionEventGeneric(Action action,
                      base::TimeTicks event_time,
                      const PointerProperties& pointer);
   MotionEventGeneric(const MotionEventGeneric& other);
 
   ~MotionEventGeneric() override;
 
   // MotionEvent implementation.
   int GetId() const override;
   Action GetAction() const override;
   int GetActionIndex() const override;
   size_t GetPointerCount() const override;
   int GetPointerId(size_t pointer_index) const override;
   float GetX(size_t pointer_index) const override;
   float GetY(size_t pointer_index) const override;
   float GetRawX(size_t pointer_index) const override;
   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 GetTilt(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;
   int GetFlags() const override;
   base::TimeTicks GetEventTime() const override;
   size_t GetHistorySize() const override;
   base::TimeTicks GetHistoricalEventTime(
       size_t historical_index) const override;
   float GetHistoricalTouchMajor(size_t pointer_index,
                                 size_t historical_index) const override;
@@ skipping 39 matching lines @@
   int action_index_;
   int button_state_;
   int flags_;
   base::StackVector<PointerProperties, kTypicalMaxPointerCount> pointers_;
   ScopedVector<MotionEvent> historical_events_;
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_GESTURE_DETECTION_UI_MOTION_EVENT_GENERIC_H_