ash: Add SessionController/Client mojo interfaces

ash/common/wm_shell.cc

Index: ash/common/wm_shell.cc
diff --git a/ash/common/wm_shell.cc b/ash/common/wm_shell.cc
index 41d6b6247421cfb9d6e448affe4665db559dab27..d7a5a91a00258cd51b5183f6dfa584c35da27301 100644
--- a/ash/common/wm_shell.cc
+++ b/ash/common/wm_shell.cc
@@ -15,6 +15,7 @@
 #include "ash/common/keyboard/keyboard_ui.h"
 #include "ash/common/new_window_client_proxy.h"
 #include "ash/common/palette_delegate.h"
+#include "ash/common/session/session_controller.h"
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shelf/app_list_shelf_item_delegate.h"
 #include "ash/common/shelf/shelf_controller.h"
@@ -259,8 +260,8 @@ WmShell::WmShell(std::unique_ptr<ShellDelegate> shell_delegate)
       system_tray_notifier_(base::MakeUnique<SystemTrayNotifier>()),
       wallpaper_delegate_(delegate_->CreateWallpaperDelegate()),
       window_cycle_controller_(base::MakeUnique<WindowCycleController>()),
-      window_selector_controller_(
-          base::MakeUnique<WindowSelectorController>()) {
+      window_selector_controller_(base::MakeUnique<WindowSelectorController>()),
+      session_controller_(base::MakeUnique<SessionController>()) {
 #if defined(OS_CHROMEOS)
   brightness_control_delegate_.reset(new system::BrightnessControllerChromeos);
   keyboard_brightness_control_delegate_.reset(new KeyboardBrightnessController);