Use moar ToXMLElement() in place of static_cast<>.

Introduces checks in a few new places, but mainly just consolidates
checking/casting logic.

Change-Id: I634a03060d254db099972c6978249992367e146c
Reviewed-on: https://pdfium-review.googlesource.com/38900
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>

1 files changed, 3 insertions, 5 deletions

diff --git a/core/fpdfdoc/cpdf_metadata.cpp b/core/fpdfdoc/cpdf_metadata.cpp
index 323de4ffcf..5ef7312752 100644
--- a/core/fpdfdoc/cpdf_metadata.cpp
+++ b/core/fpdfdoc/cpdf_metadata.cpp
@@ -49,11 +49,9 @@ void CheckForSharedFormInternal(CFX_XMLElement* element,
 
   for (auto* child = element->GetFirstChild(); child;
        child = child->GetNextSibling()) {
-    if (child->GetType() != FX_XMLNODE_Element)
-      continue;
-
-    CheckForSharedFormInternal(static_cast<CFX_XMLElement*>(child),
-                               unsupported);
+    CFX_XMLElement* pElement = ToXMLElement(child);
+    if (pElement)
+      CheckForSharedFormInternal(pElement, unsupported);
   }
 }