Make code compile with clang_use_chrome_plugin (part I)

core/fpdfapi/fpdf_page/cpdf_pageobject.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_pageobject.h"
 
 CPDF_PageObject::CPDF_PageObject() {}
 
 CPDF_PageObject::~CPDF_PageObject() {}
 
+bool CPDF_PageObject::IsText() const {
+  return false;
+}
+
+bool CPDF_PageObject::IsPath() const {
+  return false;
+}
+
+bool CPDF_PageObject::IsImage() const {
+  return false;
+}
+
+bool CPDF_PageObject::IsShading() const {
+  return false;
+}
+
+bool CPDF_PageObject::IsForm() const {
+  return false;
+}
+
+CPDF_TextObject* CPDF_PageObject::AsText() {
+  return nullptr;
+}
+
+const CPDF_TextObject* CPDF_PageObject::AsText() const {
+  return nullptr;
+}
+
+CPDF_PathObject* CPDF_PageObject::AsPath() {
+  return nullptr;
+}
+
+const CPDF_PathObject* CPDF_PageObject::AsPath() const {
+  return nullptr;
+}
+
+CPDF_ImageObject* CPDF_PageObject::AsImage() {
+  return nullptr;
+}
+
+const CPDF_ImageObject* CPDF_PageObject::AsImage() const {
+  return nullptr;
+}
+
+CPDF_ShadingObject* CPDF_PageObject::AsShading() {
+  return nullptr;
+}
+
+const CPDF_ShadingObject* CPDF_PageObject::AsShading() const {
+  return nullptr;
+}
+
+CPDF_FormObject* CPDF_PageObject::AsForm() {
+  return nullptr;
+}
+
+const CPDF_FormObject* CPDF_PageObject::AsForm() const {
+  return nullptr;
+}
+
 void CPDF_PageObject::CopyData(const CPDF_PageObject* pSrc) {
   CopyStates(*pSrc);
   m_Left = pSrc->m_Left;
   m_Right = pSrc->m_Right;
   m_Top = pSrc->m_Top;
   m_Bottom = pSrc->m_Bottom;
 }
 
 void CPDF_PageObject::TransformClipPath(CFX_Matrix& matrix) {
   if (m_ClipPath.IsNull()) {
@@ skipping 11 matching lines @@
   pGS->m_Matrix.Concat(matrix);
 }
 
 FX_RECT CPDF_PageObject::GetBBox(const CFX_Matrix* pMatrix) const {
   CFX_FloatRect rect(m_Left, m_Bottom, m_Right, m_Top);
   if (pMatrix) {
     pMatrix->TransformRect(rect);
   }
   return rect.GetOutterRect();
 }