mash: Fix system tray clock 12/24 hour time setting

ash/mus/window_manager_application.cc

Index: ash/mus/window_manager_application.cc
diff --git a/ash/mus/window_manager_application.cc b/ash/mus/window_manager_application.cc
index f55521a3a10bde17d55141b2c6478528e36c600f..f5872211858defa20b4c0a52ac10d4b21263c9b9 100644
--- a/ash/mus/window_manager_application.cc
+++ b/ash/mus/window_manager_application.cc
@@ -11,6 +11,7 @@
 #include "ash/mus/accelerators/accelerator_registrar_impl.h"
 #include "ash/mus/native_widget_factory_mus.h"
 #include "ash/mus/shelf_delegate_mus.h"
+#include "ash/mus/system_tray_delegate_mus.h"
 #include "ash/mus/wallpaper_delegate_mus.h"
 #include "ash/mus/window_manager.h"
 #include "base/bind.h"
@@ -155,6 +156,7 @@ void WindowManagerApplication::OnStart(const shell::Identity& identity) {
 bool WindowManagerApplication::OnConnect(const shell::Identity& remote_identity,
                                          shell::InterfaceRegistry* registry) {
   registry->AddInterface<ash::mojom::ShelfController>(this);
+  registry->AddInterface<ash::mojom::SystemTray>(this);
   registry->AddInterface<ash::mojom::WallpaperController>(this);
   registry->AddInterface<ui::mojom::AcceleratorRegistrar>(this);
   if (remote_identity.name() == "mojo:mash_session") {
@@ -174,6 +176,14 @@ void WindowManagerApplication::Create(
   shelf_controller_bindings_.AddBinding(shelf_controller, std::move(request));
 }
 
+void WindowManagerApplication::Create(const shell::Identity& remote_identity,
+                                      ash::mojom::SystemTrayRequest request) {
+  ash::mojom::SystemTray* system_tray = static_cast<SystemTrayDelegateMus*>(

[sky, 2016/09/19 23:47:52]

This cast makes me nervous. Could you cache the SystemTrayDelegateMus one some
where so you don't need the cast?

[James Cook, 2016/09/20 01:52:11]

How's this? I looked at caching the pointer, but it's pretty awkward.
ShellDelegateMus creates it. But ShellDelegateMus is stored as-a ShellDelegate
in WmShell. So I'd have to cache a ShellDelegateMus* in WmShellMus. WmShellMus's
constructor looks like this:

WmShellMus::WmShellMus(unique_ptr<ShellDelegate> delegate)
  : WmShell(std::move(delegate)) {}

I could change |delegate| to ShellDelegateMus* and cache it and take ownership,
but then we lose unique_ptr as a sign of ownership transfer. Or I could pass
both a unique_ptr and a raw pointer, which is just bizarre. Or I could cast
WmShell::delegate() to a ShellDelegateMus... which is a static_cast<> again.
Yuck.

+      WmShell::Get()->system_tray_delegate());
+  DCHECK(system_tray);
+  system_tray_bindings_.AddBinding(system_tray, std::move(request));
+}
+
 void WindowManagerApplication::Create(
     const ::shell::Identity& remote_identity,
     ash::mojom::WallpaperControllerRequest request) {