Move geometry interface files to geometry directory.

third_party/WebKit/Source/core/geometry/DOMQuad.idl

 // Copyright 2017 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.
 
 // https://drafts.fxtf.org/geometry/#domquad
 
 [
  Constructor(optional DOMPointInit p1, optional DOMPointInit p2,
                   optional DOMPointInit p3, optional DOMPointInit p4),
  Exposed=(Window,Worker),
  RuntimeEnabled=GeometryInterfaces
 ]
 interface DOMQuad {
     [NewObject] static DOMQuad fromRect(optional DOMRectInit other);
     [NewObject] static DOMQuad fromQuad(optional DOMQuadInit other);
 
     [SameObject] readonly attribute DOMPoint p1;
     [SameObject] readonly attribute DOMPoint p2;
     [SameObject] readonly attribute DOMPoint p3;
     [SameObject] readonly attribute DOMPoint p4;
     [NewObject] DOMRect getBounds();
 
     serializer = { attribute };
 };