ash: Rename LauncherModel to ShelfModel.

ash/test/test_shell_delegate.cc

Index: ash/test/test_shell_delegate.cc
diff --git a/ash/test/test_shell_delegate.cc b/ash/test/test_shell_delegate.cc
index 735ad6039935fe3de812d2f45e13f4942e0ab4e3..8a4970c85b22a1a56a90c2bfd1ca7395c2b6d70a 100644
--- a/ash/test/test_shell_delegate.cc
+++ b/ash/test/test_shell_delegate.cc
@@ -98,8 +98,7 @@ app_list::AppListViewDelegate* TestShellDelegate::CreateAppListViewDelegate() {
   return NULL;
 }
 
-LauncherDelegate* TestShellDelegate::CreateLauncherDelegate(
-    ash::LauncherModel* model) {
+LauncherDelegate* TestShellDelegate::CreateLauncherDelegate(ShelfModel* model) {
   return new TestLauncherDelegate(model);
 }