Added experimental tilt and tiltDirection to the Touch interface

Source/web/WebInputEventConversion.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 419 matching lines @@
 
     // This assumes convertFromContainingWindow does only translations, not scales.
     FloatPoint floatPos = convertHitPointToWindow(widget, point.position);
     IntPoint flooredPoint = flooredIntPoint(floatPos);
     m_pos = widget->convertFromContainingWindow(flooredPoint) + (floatPos - flooredPoint);
 
     m_screenPos = FloatPoint(point.screenPosition.x, point.screenPosition.y);
     m_radius = scaleSizeToWindow(widget, FloatSize(point.radiusX, point.radiusY));
     m_rotationAngle = point.rotationAngle;
     m_force = point.force;
+    m_tilt = point.tilt;
+    m_tiltDirection = point.tiltDirection;

[Rick Byers, 2015/02/13 08:48:05]

Your spec should clarify whether this is intended to take transforms into
account.  Eg. I assume the '0X' axis is relative to current screen rotation. 
But it's physical screen orientation it's relative to, not the co-ordinate
system of the input co-ordinates, right?  Eg. what if I'm receiving the events
inside of an iframe whcih is being spun with a rotation transform.

[d.pikalov, 2015/02/13 13:31:17]

Right, I updated spec with "...angle in relation to the 0X axis of the current
screen orientation..."

 }
 
 PlatformTouchEventBuilder::PlatformTouchEventBuilder(Widget* widget, const WebTouchEvent& event)
 {
     m_type = toPlatformTouchEventType(event.type);
     m_modifiers = toPlatformEventModifiers(event.modifiers);
     m_timestamp = event.timeStampSeconds;
 
     for (unsigned i = 0; i < event.touchesLength; ++i)
         m_touchPoints.append(PlatformTouchPointBuilder(widget, event.touches[i]));
@@ skipping 354 matching lines @@
     modifiers = getWebInputModifiers(event);
 
     globalX = event.screenX();
     globalY = event.screenY();
     IntPoint localPoint = convertAbsoluteLocationForRenderObject(event.absoluteLocation(), *renderObject);
     x = localPoint.x();
     y = localPoint.y();
 }
 
 } // namespace blink