Don't focus on the detach button on click

This way, we can maintain the selection when detaching the composer.

src/client/composer/composer-embed.vala

@@ -63,10 +63,17 @@ public class ComposerEmbed : Gtk.Bin, ComposerContainer {
             on_focus_out();
         composer.editor.focus_in_event.disconnect(on_focus_in);
         composer.editor.focus_out_event.disconnect(on_focus_out);
+        Gtk.Widget focus = top_window.get_focus();
         
         remove(composer);
-        new ComposerWindow(composer);
+        ComposerWindow window = new ComposerWindow(composer);
-        composer.set_focus();
+        if (focus != null) {
+            ComposerWindow focus_win = focus.get_toplevel() as ComposerWindow;
+            if (focus_win != null && focus_win == window)
+                focus.grab_focus();
+        } else {
+            composer.set_focus();
+        }
         close();
     }
     

ui/composer.glade

@@ -629,6 +629,7 @@
                 <property name="visible">True</property>
                 <property name="can_focus">True</property>
                 <property name="receives_default">True</property>
+                <property name="focus_on_click">False</property>
               </object>
               <packing>
                 <property name="expand">False</property>