PDF: Consistently pass FPDF handles by value.

pdf/pdfium/fuzzers/pdfium_fuzzer_helper.cc

Index: pdf/pdfium/fuzzers/pdfium_fuzzer_helper.cc
diff --git a/pdf/pdfium/fuzzers/pdfium_fuzzer_helper.cc b/pdf/pdfium/fuzzers/pdfium_fuzzer_helper.cc
index 9598caa40e575ddff1f4cc339c09d54645f81bf8..d15d621b89ca66f9594152867ba2c437e12d0cbc 100644
--- a/pdf/pdfium/fuzzers/pdfium_fuzzer_helper.cc
+++ b/pdf/pdfium/fuzzers/pdfium_fuzzer_helper.cc
@@ -192,8 +192,8 @@ void PDFiumFuzzerHelper::RenderPdf(const char* pBuf, size_t len) {
   FORM_DoDocumentAAction(form.get(), FPDFDOC_AACTION_WC);
 }
 
-bool PDFiumFuzzerHelper::RenderPage(const FPDF_DOCUMENT& doc,
-                                    const FPDF_FORMHANDLE& form,
+bool PDFiumFuzzerHelper::RenderPage(FPDF_DOCUMENT doc,
+                                    FPDF_FORMHANDLE form,
                                     const int page_index) {
   std::unique_ptr<void, FPDFPageDeleter> page(FPDF_LoadPage(doc, page_index));
   if (!page)