Add FPDF_ANNOT in PDFiumEngine::GetRenderingFlags.

pdf/pdfium/pdfium_engine.h

Index: pdf/pdfium/pdfium_engine.h
diff --git a/pdf/pdfium/pdfium_engine.h b/pdf/pdfium/pdfium_engine.h
index c7bf28e204d09f6694848e433c2ef5512e39d008..07c15b56e865c9dca7c344e278c244c3028adc45 100644
--- a/pdf/pdfium/pdfium_engine.h
+++ b/pdf/pdfium/pdfium_engine.h
@@ -699,6 +699,9 @@ class PDFiumEngine : public PDFEngine,
   // Whether to render in grayscale or in color.
   bool render_grayscale_;
 
+  // Whether to render PDF annotations.
+  bool render_annots_;
+
   // The link currently under the cursor.
   std::string link_under_cursor_;