Plumbing stylus tilt for Mac

content/browser/renderer_host/input/web_input_event_builders_mac.mm

 // Copyright 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.
 
 /*
  * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2006-2009 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ skipping 395 matching lines @@
   // For all other tablet events, the pointer type will be just pen.
   NSEventSubtype subtype = [event subtype];
   if (subtype == NSTabletPointEventSubtype ||
       subtype == NSTabletProximityEventSubtype) {
     result.pointerType = blink::WebPointerProperties::PointerType::Pen;
   } else {
     result.pointerType = blink::WebPointerProperties::PointerType::Mouse;
   }
   result.id = [event deviceID];
   result.force = [event pressure];
+  NSPoint tilt = [event tilt];
+  result.tiltX = lround(tilt.x * 90);
+  result.tiltY = lround(tilt.y * 90);
   return result;
 }
 
 // WebMouseWheelEvent ---------------------------------------------------------
 
 blink::WebMouseWheelEvent WebMouseWheelEventBuilder::Build(
     NSEvent* event,
     NSView* view) {
   blink::WebMouseWheelEvent result;
 
@@ skipping 181 matching lines @@
       break;
     default:
       NOTIMPLEMENTED();
       result.type = blink::WebInputEvent::Undefined;
   }
 
   return result;
 }
 
 }  // namespace content