Update pdfium binaries for Windows builds

It fixes rendering problems with newer PDFs.

dependencies/pdfium/win/public/fpdf_attachment.h

@@ -172,6 +172,23 @@ FPDFAttachment_GetFile(FPDF_ATTACHMENT attachment,
                        unsigned long buflen,
                        unsigned long* out_buflen);
 
+// Experimental API.
+// Get the MIME type (Subtype) of the embedded file |attachment|. |buffer| is
+// only modified if |buflen| is longer than the length of the MIME type string.
+// If the Subtype is not found or if there is no file stream, an empty string
+// would be copied to |buffer| and the return value would be 2. On other errors,
+// nothing would be added to |buffer| and the return value would be 0.
+//
+//   attachment - handle to an attachment.
+//   buffer     - buffer for holding the MIME type string encoded in UTF-16LE.
+//   buflen     - length of the buffer in bytes.
+//
+// Returns the length of the MIME type string in bytes.
+FPDF_EXPORT unsigned long FPDF_CALLCONV
+FPDFAttachment_GetSubtype(FPDF_ATTACHMENT attachment,
+                          FPDF_WCHAR* buffer,
+                          unsigned long buflen);
+
 #ifdef __cplusplus
 }  // extern "C"
 #endif  // __cplusplus