Return retained objects from CPDF_Image and CPDF_Page methods.

Change-Id: Ifa5a6708a18a68bc9a1557786b7da88f458b9dc0
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/98470
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>
diff --git a/fpdfsdk/fpdf_editimg.cpp b/fpdfsdk/fpdf_editimg.cpp
index f4378a9..3c41243 100644
--- a/fpdfsdk/fpdf_editimg.cpp
+++ b/fpdfsdk/fpdf_editimg.cpp
@@ -312,7 +312,7 @@
   if (!pImg)
     return 0;
 
-  const CPDF_Dictionary* pDict = pImg->GetDict();
+  RetainPtr<const CPDF_Dictionary> pDict = pImg->GetDict();
   if (!pDict)
     return 0;
 
@@ -338,7 +338,8 @@
     return 0;
 
   CPDF_PageObject* pObj = CPDFPageObjectFromFPDFPageObject(image_object);
-  const CPDF_Dictionary* pDict = pObj->AsImage()->GetImage()->GetDict();
+  RetainPtr<const CPDF_Dictionary> pDict =
+      pObj->AsImage()->GetImage()->GetDict();
   RetainPtr<const CPDF_Object> pFilter = pDict->GetDirectObjectFor("Filter");
   ByteString bsFilter = pFilter->IsName()
                             ? pFilter->AsName()->GetString()