Make code compile with clang_use_chrome_plugin (part I)

core/fpdfapi/fpdf_page/cpdf_imageobject.cpp

 // Copyright 2016 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "core/fpdfapi/fpdf_page/include/cpdf_imageobject.h"
 
 #include "core/fpdfapi/fpdf_page/include/cpdf_image.h"
 #include "core/fpdfapi/fpdf_page/pageint.h"
@@ skipping 15 matching lines @@
 
 CPDF_ImageObject* CPDF_ImageObject::Clone() const {
   CPDF_ImageObject* obj = new CPDF_ImageObject;
   obj->CopyData(this);
 
   obj->m_pImage = m_pImage->Clone();
   obj->m_Matrix = m_Matrix;
   return obj;
 }
 
+CPDF_PageObject::Type CPDF_ImageObject::GetType() const {
+  return IMAGE;
+}
+
 void CPDF_ImageObject::Transform(const CFX_Matrix& matrix) {
   m_Matrix.Concat(matrix);
   CalcBoundingBox();
 }
 
+bool CPDF_ImageObject::IsImage() const {
+  return true;
+}
+
+CPDF_ImageObject* CPDF_ImageObject::AsImage() {
+  return this;
+}
+
+const CPDF_ImageObject* CPDF_ImageObject::AsImage() const {
+  return this;
+}
+
 void CPDF_ImageObject::CalcBoundingBox() {
   m_Left = m_Bottom = 0;
   m_Right = m_Top = 1.0f;
   m_Matrix.TransformRect(m_Left, m_Right, m_Top, m_Bottom);
 }