Use figure dimensions for other image objects in Previewer (#397)

# Pull Request

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- Companion of
insightsengineering/teal.modules.general#884

---------

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

Author: averissimo

DESCRIPTION

@@ -84,4 +84,4 @@ Encoding: UTF-8
 Language: en-US
 LazyData: true
 Roxygen: list(markdown = TRUE)
-RoxygenNote: 7.3.2
+RoxygenNote: 7.3.3

R/toHTML.R

@@ -77,17 +77,19 @@ toHTML.default <- function(x, ...) {
 #' @keywords internal
 .toHTML.gg <- function(x, ...) {
   on.exit(unlink(tmpfile))
+  dims <- resolve_figure_dimensions(x, convert_to_inches = TRUE, dpi = 100)
   tmpfile <- tempfile(fileext = ".png")
-  ggplot2::ggsave(tmpfile, plot = x, width = 5, height = 4, dpi = 100)
+  ggplot2::ggsave(tmpfile, plot = x, width = dims$width, height = dims$height, dpi = 100)
   shiny::tags$img(src = knitr::image_uri(tmpfile))
 }
 
 #' @method .toHTML grob
 #' @keywords internal
 .toHTML.grob <- function(x, ...) {
   on.exit(unlink(tmpfile))
+  dims <- resolve_figure_dimensions(x)
   tmpfile <- tempfile(fileext = ".png")
-  grDevices::png(filename = tmpfile)
+  grDevices::png(filename = tmpfile, width = dims$width, height = dims$height)
   grid::grid.newpage()
   grid::grid.draw(x)
   grDevices::dev.off()