Log message when XFA load fails

samples/pdfium_test.cc

Index: samples/pdfium_test.cc
diff --git a/samples/pdfium_test.cc b/samples/pdfium_test.cc
index 665849da432f75dfb2ee862b002539fa78a956cf..d01602fc8547398b6f54ab842a816a3351d79b19 100644
--- a/samples/pdfium_test.cc
+++ b/samples/pdfium_test.cc
@@ -291,7 +291,9 @@ void RenderPdf(const char* name, const char* pBuf, size_t len,
   (void) FPDFAvail_IsFormAvail(pdf_avail, &hints);
 
   FPDF_FORMHANDLE form = FPDFDOC_InitFormFillEnvironment(doc, &form_callbacks);
-  FPDF_LoadXFA(doc);
+  if (!FPDF_LoadXFA(doc)) {
+    printf("LoadXFA unsuccessful, continuing anyway.\n");
+  }
   FPDF_SetFormFieldHighlightColor(form, 0, 0xFFE4DD);
   FPDF_SetFormFieldHighlightAlpha(form, 100);