[geary] Fix message body webview sometimes not stopping getting taller

[Michael Gratton <mjog src gnome org>]

commit 1d15de114a7abf82401fe5caa1c946fe2d3ee65e
Author: Michael Gratton <mike vee net>
Date:   Wed Nov 28 21:55:41 2018 +1100

    Fix message body webview sometimes not stopping getting taller

 src/client/components/client-web-view.vala | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/client/components/client-web-view.vala b/src/client/components/client-web-view.vala
index 3b375d98..fb6656b7 100644
--- a/src/client/components/client-web-view.vala
+++ b/src/client/components/client-web-view.vala
@@ -205,7 +205,7 @@ public class ClientWebView : WebKit.WebView, Geary.BaseInterface {
     /** The HTML content's current preferred height in window pixels. */
     public int preferred_height {
         get {
-            return (int) GLib.Math.ceil(
+            return (int) GLib.Math.round(
                 this.webkit_reported_height * this.zoom_level
             );
         }