[fractal/zbrown/message-margin] Only add margin to the start of message rows

[Zander <zbrown src gnome org>]

commit cd750dec44e59af8546066bf2d196dcf63d578b1
Author: Zander Brown <zbrown gnome org>
Date:   Wed Apr 3 21:50:30 2019 +0100

    Only add margin to the start of message rows
    
    Allows text to flow right to the edge, important on smaller devices
    
    Also avoids use of child properties which are going away soon

 fractal-gtk/src/widgets/message.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/fractal-gtk/src/widgets/message.rs b/fractal-gtk/src/widgets/message.rs
index e01090a6..dcae84ef 100644
--- a/fractal-gtk/src/widgets/message.rs
+++ b/fractal-gtk/src/widgets/message.rs
@@ -126,7 +126,9 @@ impl MessageBox {
         // +--------+---------+
         let msg_widget = gtk::Box::new(gtk::Orientation::Horizontal, 5);
         let content = self.build_room_msg_content(msg, true);
-        msg_widget.pack_start(&content, true, true, 50);
+        content.set_margin_start(50);
+
+        msg_widget.pack_start(&content, true, true, 0);
 
         msg_widget
     }
@@ -221,7 +223,7 @@ impl MessageBox {
         w.set_justify(gtk::Justification::Left);
         w.set_xalign(0.0);
         w.set_valign(gtk::Align::Start);
-        w.set_halign(gtk::Align::Start);
+        w.set_halign(gtk::Align::Fill);
         w.set_selectable(true);
     }