mash: Refactor ChromeLauncherController's ShelfDelegate code.

chrome/browser/ui/ash/launcher/launcher_context_menu.cc

Index: chrome/browser/ui/ash/launcher/launcher_context_menu.cc
diff --git a/chrome/browser/ui/ash/launcher/launcher_context_menu.cc b/chrome/browser/ui/ash/launcher/launcher_context_menu.cc
index 5852c2339385f639e9383573dd4e507a9ccb3faa..4ddb2a73b5fe964feabc8aebed974b401407bb9a 100644
--- a/chrome/browser/ui/ash/launcher/launcher_context_menu.cc
+++ b/chrome/browser/ui/ash/launcher/launcher_context_menu.cc
@@ -127,7 +127,10 @@ void LauncherContextMenu::ExecuteCommand(int command_id, int event_flags) {
           ash::UMA_CLOSE_THROUGH_CONTEXT_MENU);
       break;
     case MENU_PIN:
-      controller_->TogglePinned(item_.id);
+      if (controller_->IsAppPinned(item_.app_launch_id.app_id()))
+        controller_->UnpinAppWithID(item_.app_launch_id.app_id());
+      else
+        controller_->PinAppWithID(item_.app_launch_id.app_id());
       break;
     case MENU_AUTO_HIDE:
       wm_shelf_->SetAutoHideBehavior(