[css-typed-om] remove asMatrix() method in CSSTransformComponent.idl

third_party/WebKit/Source/core/css/cssom/CSSTransformComponent.idl

 // Copyright 2016 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.
 
 // CSSTransformComponent is the base class used for the representations of
 // the individual CSS transforms. They are combined in a CSSTransformValue
 // before they can be used as a value for properties like "transform".
 // Spec: https://drafts.css-houdini.org/css-typed-om/#csstransformcomponent
 [
     Exposed=(Window,PaintWorklet),
     RuntimeEnabled=CSSTypedOM,
 ] interface CSSTransformComponent {
     stringifier;
     boolean is2D();
-    CSSMatrixComponent asMatrix();
 };