Address BDR's email about preferring png() when aqua capabilities are available

Also, prefer jpeg over Cairo since it doesn't really matter what device we use, and it seems Cairo will need to be reinstalled in R 4.1 for it to work

Author: cpsievert

R/ggplotly.R

@@ -176,12 +176,12 @@ gg2list <- function(p, width = NULL, height = NULL,
 
   # To convert relative sizes correctly, we use grid::convertHeight(),
   # which requires a known output (device) size.
-  dev_fun <- if (system.file(package = "Cairo") != "") {
-    Cairo::Cairo
-  } else if (capabilities("png")) {
+  dev_fun <- if (capabilities("aqua") || capabilities("png")) {
     grDevices::png
   } else if (capabilities("jpeg")) {
     grDevices::jpeg 
+  } else if (system.file(package = "Cairo") != "") {
+    Cairo::Cairo
   } else {
     stop(
       "No Cairo or bitmap device is available. Such a graphics device is required to convert sizes correctly in ggplotly().\n\n",