Add type cast definitions for CPDF_Dictionary.

This CL adds ToCPDFDictionary type definitions and updates one file to use
instead of straight casts. I had to fix two places where we'd casted off the
constness of the original pointer.

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

Review URL: https://codereview.chromium.org/1399233003 .

1 files changed, 5 insertions, 8 deletions

diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_document.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_document.cpp
index 2dff766187..29c1a007cf 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_document.cpp
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_document.cpp
@@ -143,18 +143,15 @@ CPDF_Dictionary* CPDF_Document::GetPage(int iPage) {
     return nullptr;
 
   if (m_bLinearized && (iPage == (int)m_dwFirstPageNo)) {
-    CPDF_Object* pObj = GetIndirectObject(m_dwFirstPageObjNum);
-    if (pObj && pObj->GetType() == PDFOBJ_DICTIONARY) {
-      return static_cast<CPDF_Dictionary*>(pObj);
-    }
+    if (CPDF_Dictionary* pDict =
+            ToDictionary(GetIndirectObject(m_dwFirstPageObjNum)))
+      return pDict;
   }
 
   int objnum = m_PageList.GetAt(iPage);
   if (objnum) {
-    CPDF_Object* pObj = GetIndirectObject(objnum);
-    if (pObj && pObj->GetType() == PDFOBJ_DICTIONARY) {
-      return static_cast<CPDF_Dictionary*>(pObj);
-    }
+    if (CPDF_Dictionary* pDict = ToDictionary(GetIndirectObject(objnum)))
+      return pDict;
   }
 
   CPDF_Dictionary* pRoot = GetRoot();