Make Document.createTouch arguments non-optional

third_party/WebKit/Source/core/dom/Document.idl

 /*
  * Copyright (C) 2006, 2007, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006, 2007 Samuel Weinig <sam@webkit.org>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 138 matching lines @@
     readonly attribute Element? scrollingElement;
 
     // Pointer Lock
     // https://w3c.github.io/pointerlock/#extensions-to-the-document-interface
     attribute EventHandler onpointerlockchange;
     attribute EventHandler onpointerlockerror;
     [MeasureAs=DocumentExitPointerLock] void exitPointerLock();
 
     // Touch Events
     // https://w3c.github.io/touch-events/#extensions-to-the-document-interface
-    // FIXME: The arguments should not be optional.
+    // TODO(lunalu): The spec uses the WindowProxy type for view.
     [RuntimeEnabled=TouchEventFeatureDetection, Measure, LegacyInterfaceTypeChecking, Custom=CallPrologue]
-    Touch createTouch([Default=Undefined] optional Window window,
-                      [Default=Undefined] optional EventTarget target,
-                      [Default=Undefined] optional long identifier,
-                      [Default=Undefined] optional unrestricted double pageX,
-                      [Default=Undefined] optional unrestricted double pageY,
-                      [Default=Undefined] optional unrestricted double screenX,
-                      [Default=Undefined] optional unrestricted double screenY,
+    Touch createTouch(Window view,
+                      EventTarget target,
+                      long identifier,
+                      double pageX,
+                      double pageY,
+                      double screenX,
+                      double screenY,
                       [Default=Undefined] optional unrestricted double radiusX,

[foolip, 2017/03/21 08:01:13]

Can you change these to "optional unrestricted double radiusX = 0" and similar
to get rid of the remaining [Default=Undefined] here?

[lunalu1, 2017/03/21 19:19:27]

OK. The spec didn't mention these arguments. So maybe we should confirm with the
someone on the team if this is safe to do? 

[foolip, 2017/03/22 05:16:24]

The generated code will be slightly different, but it'll amount to the same
thing, so it's a safe change to make.

                       [Default=Undefined] optional unrestricted double radiusY,
                       [Default=Undefined] optional unrestricted float rotationAngle,
                       [Default=Undefined] optional unrestricted float force);
     [RuntimeEnabled=TouchEventFeatureDetection] TouchList createTouchList(Touch... touches);
 
     // Custom Elements
     // https://w3c.github.io/webcomponents/spec/custom/#extensions-to-document-interface-to-register
     // FIXME: The registerElement return type should be Function.
     [CallWith=ScriptState, CustomElementCallbacks, RaisesException, MeasureAs=DocumentRegisterElement] CustomElementConstructor registerElement(DOMString type, optional ElementRegistrationOptions options);
     // https://w3c.github.io/webcomponents/spec/custom/#extensions-to-document-interface-to-instantiate
@@ skipping 30 matching lines @@
     [RuntimeEnabled=ExperimentalContentSecurityPolicyFeatures] attribute EventHandler onsecuritypolicyviolation;
     attribute EventHandler onselectionchange;
     attribute EventHandler onselectstart;
     attribute EventHandler onwheel;
 };
 
 Document implements GlobalEventHandlers;
 Document implements ParentNode;
 Document implements NonElementParentNode;
 Document implements DocumentOrShadowRoot;