Remove unused TransformOperation::isIdentity

Source/platform/transforms/IdentityTransformOperation.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * 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
@@ skipping 24 matching lines @@
     {
         return adoptRef(new IdentityTransformOperation());
     }
 
     virtual bool canBlendWith(const TransformOperation& other) const
     {
         return isSameType(other);
     }
 
 private:
-    virtual bool isIdentity() const OVERRIDE FINAL { return true; }
     virtual OperationType type() const OVERRIDE { return Identity; }
 
     virtual bool operator==(const TransformOperation& o) const OVERRIDE
     {
         return isSameType(o);
     }
 
     virtual void apply(TransformationMatrix&, const FloatSize&) const OVERRIDE { }
 
     virtual PassRefPtr<TransformOperation> blend(const TransformOperation*, double, bool = false) OVERRIDE
     {
         return this;
     }
 
     IdentityTransformOperation()
     {
     }
 
 };
 
 } // namespace blink
 
 #endif // IdentityTransformOperation_h