Fix //third_party/cec to not disable -Wunused-function.

ui/aura/mus/window_tree_client_unittest.cc

Index: ui/aura/mus/window_tree_client_unittest.cc
diff --git a/ui/aura/mus/window_tree_client_unittest.cc b/ui/aura/mus/window_tree_client_unittest.cc
index ae2802e1e1919be6b8309af5d86afa289005ff98..15adabeaf7d00926359e2f7002080377a9204c05 100644
--- a/ui/aura/mus/window_tree_client_unittest.cc
+++ b/ui/aura/mus/window_tree_client_unittest.cc
@@ -58,10 +58,6 @@ void SetWindowVisibility(Window* window, bool visible) {
     window->Hide();
 }
 
-Window* GetFirstRoot(WindowTreeClient* client) {
-  return client->GetRoots().empty() ? nullptr : *client->GetRoots().begin();
-}
-
 bool IsWindowHostVisible(Window* window) {
   return window->GetRootWindow()->GetHost()->compositor()->IsVisible();
 }
@@ -441,22 +437,6 @@ TEST_F(WindowTreeClientWmTest, SetVisibleFailedWithPendingChange) {
   EXPECT_EQ(original_visible, root_window()->TargetVisibility());
 }
 
-/*
-// Verifies |is_modal| is reverted if the server replied that the change failed.
-TEST_F(WindowTreeClientWmTest, SetModalFailed) {
-  WindowTreeSetup setup;
-  Window* root = GetFirstRoot();
-  ASSERT_TRUE(root);
-  EXPECT_FALSE(root->is_modal());
-  root->SetModal();
-  uint32_t change_id;
-  ASSERT_TRUE(window_tree()->GetAndClearChangeId(&change_id));
-  EXPECT_TRUE(root->is_modal());
-  window_tree_client()->OnChangeCompleted(change_id, false);
-  EXPECT_FALSE(root->is_modal());
-}
-*/
-
 namespace {
 
 class InputEventBasicTestWindowDelegate : public test::TestWindowDelegate {