Can't press A or Delete to archive/trash message: Closes bgo#721789

If compiled with the GDK binding fix in Vala 0.23.2 (bgo#713240), this
patch fixes the accelerator problem.

Tip o' the hat to Charles, who pointed out the accelerators.ui file.

src/client/application/geary-controller.vala

@@ -7,6 +7,8 @@
 // Primary controller object for Geary.
 public class GearyController : Geary.BaseObject {
     // Named actions.
+    //
+    // NOTE: Some actions with accelerators need to also be added to ui/accelerators.ui
     public const string ACTION_HELP = "GearyHelp";
     public const string ACTION_ABOUT = "GearyAbout";
     public const string ACTION_DONATE = "GearyDonate";

ui/accelerators.ui

@@ -1,5 +1,7 @@
 <ui>
     <accelerator action="GearyNewMessage" />
+    <accelerator action="GearyArchiveMessage" />
+    <accelerator action="GearyTrashMessage" />
     <accelerator action="GearyDeleteMessage" />
     <accelerator action="GearyReplyToMessage" />
     <accelerator action="GearyReplyAllMessage" />