Add tangentialPressure and twist properties to PointerEvent on Mac

third_party/WebKit/public/platform/WebPointerProperties.h

 // Copyright (c) 2015 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 WebPointerProperties_h
 #define WebPointerProperties_h
 
 #include <cstdint>
 #include <limits>
 
 namespace blink {
 
 // This class encapsulates the properties that are common between mouse and
 // pointer events and touch points as we transition towards the unified pointer
 // event model.
 // TODO(e_hakkinen): Replace WebTouchEvent with WebPointerEvent, remove
 // WebTouchEvent and WebTouchPoint and merge this into WebPointerEvent.
 class WebPointerProperties {
  public:
   WebPointerProperties()
       : id(0),
         force(std::numeric_limits<float>::quiet_NaN()),
         tiltX(0),
         tiltY(0),
+        tangentialPressure(0.0f),
+        twist(0),
         button(Button::NoButton),
         pointerType(PointerType::Unknown) {}
 
   enum class Button { NoButton = -1, Left, Middle, Right, X1, X2, Eraser };
 
   enum class Buttons : unsigned {
     NoButton = 0,
     Left = 1 << 0,
     Right = 1 << 1,
     Middle = 1 << 2,
@@ skipping 16 matching lines @@
   // The valid range is [0,1], with NaN meaning pressure is not supported by
   // the input device.
   float force;
 
   // Tilt of a pen stylus from surface normal as plane angles in degrees,
   // Values lie in [-90,90]. A positive tiltX is to the right and a positive
   // tiltY is towards the user.
   int tiltX;
   int tiltY;
 
+  // The normalized tangential pressure, typically set by an additional control
+  // of the stylus, which has a range of [-1,1], where 0 is the neutral
+  // position of the control. Alwasy 0 if the device does not support it.

[mustaq, 2017/01/03 19:09:24]

Please also add "(or barrel pressure)" in the first line. "Barrel" seems more
intuitive to me.

Also a nit: s/Alwasy/Always/.

[lanwei, 2017/01/05 16:13:41]

Done.

+  float tangentialPressure;
+
+  // The clockwise rotation of a pen stylus around its own major axis, in
+  // degrees of a range of [0,359]). Alwasy 0 if the device does not support

[mustaq, 2017/01/03 19:09:24]

Nit: "in degrees in the range [0,359]."

[lanwei, 2017/01/05 16:13:41]

Done.

+  // it.
+  int twist;
+
   Button button;
   PointerType pointerType;
 };
 
 }  // namespace blink
 
 #endif