Mege to XFA: Redo CPDF_PageObjects - part 1

Original Review URL: https://codereview.chromium.org/1601093009 .
(cherry picked from commit da9355139b5dce270be02af31db326d60f488e8c)

Trivial conflicts/changes in fpdfeditpage.cpp and fpdfxfa_page.cpp.

TBR=ochang@chromium.org

Review URL: https://codereview.chromium.org/1613823003 .
diff --git a/fpdfsdk/src/fpdfview.cpp b/fpdfsdk/src/fpdfview.cpp
index a6c1420..a4f345e 100644
--- a/fpdfsdk/src/fpdfview.cpp
+++ b/fpdfsdk/src/fpdfview.cpp
@@ -493,7 +493,7 @@
     return NULL;
   CPDF_Page* pPage = new CPDF_Page;
   pPage->Load(pDoc, pDict);
-  pPage->ParseContent();
+  pPage->ParseContent(nullptr);
   return pPage;
 #endif  // PDF_ENABLE_XFA
 }