Merge to XFA: Revert "Revert "Add type cast definitions for CPDF_Reference.""

This reverts commit 7e155865c90cc1115cc7193b7646a341d8f9093e.

Add type cast definitions for CPDF_Reference.

This Cl adds ToReference, CPDF_Object::AsReference and CPDF_Object::IsReference
and updates the src to use them as needed.

BUG=pdfium:201
R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1418923005 .

(cherry picked from commit 6ee3484bcb413f4cce303e237fe15e2bdaf51ade)

Review URL: https://codereview.chromium.org/1410073007 .

1 files changed, 15 insertions, 38 deletions

diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_parser.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_parser.cpp
index 3295b7f9e0..b12a65a844 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_parser.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_parser.cpp
@@ -671,51 +671,28 @@ void CPDF_StreamContentParser::Handle_ExecuteXObject() {
   CFX_ByteString name = GetString(0);
   if (name == m_LastImageName && m_pLastImage && m_pLastImage->GetStream() &&
       m_pLastImage->GetStream()->GetObjNum()) {
-    AddImage(NULL, m_pLastImage, FALSE);
+    AddImage(nullptr, m_pLastImage, FALSE);
     return;
   }
+
   if (m_Options.m_bTextOnly) {
-    CPDF_Object* pRes = NULL;
-    if (m_pResources == NULL) {
+    if (!m_pResources)
       return;
-    }
-    if (m_pResources == m_pPageResources) {
-      CPDF_Dictionary* pList = m_pResources->GetDict(FX_BSTRC("XObject"));
-      if (pList == NULL) {
-        return;
-      }
-      pRes = pList->GetElement(name);
-      if (pRes == NULL || pRes->GetType() != PDFOBJ_REFERENCE) {
-        return;
-      }
-    } else {
-      CPDF_Dictionary* pList = m_pResources->GetDict(FX_BSTRC("XObject"));
-      if (pList == NULL) {
-        if (m_pPageResources == NULL) {
-          return;
-        }
-        CPDF_Dictionary* pList = m_pPageResources->GetDict(FX_BSTRC("XObject"));
-        if (pList == NULL) {
-          return;
-        }
-        pRes = pList->GetElement(name);
-        if (pRes == NULL || pRes->GetType() != PDFOBJ_REFERENCE) {
-          return;
-        }
-      } else {
-        pRes = pList->GetElement(name);
-        if (pRes == NULL || pRes->GetType() != PDFOBJ_REFERENCE) {
-          return;
-        }
-      }
-    }
+
+    CPDF_Dictionary* pList = m_pResources->GetDict(FX_BSTRC("XObject"));
+    if (!pList && m_pPageResources && m_pResources != m_pPageResources)
+      pList = m_pPageResources->GetDict(FX_BSTRC("XObject"));
+    if (!pList)
+      return;
+    CPDF_Reference* pRes = ToReference(pList->GetElement(name));
+    if (!pRes)
+      return;
+
     FX_BOOL bForm;
-    if (m_pDocument->IsFormStream(((CPDF_Reference*)pRes)->GetRefObjNum(),
-                                  bForm) &&
-        !bForm) {
+    if (m_pDocument->IsFormStream(pRes->GetRefObjNum(), bForm) && !bForm)
       return;
-    }
   }
+
   CPDF_Stream* pXObject = ToStream(FindResourceObj(FX_BSTRC("XObject"), name));
   if (!pXObject) {
     m_bResourceMissing = TRUE;