Update from https://crrev.com/304418

cc/trees/layer_tree_host_unittest_context.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/trees/layer_tree_host.h"
 
 #include "base/basictypes.h"
 #include "cc/layers/content_layer.h"
 #include "cc/layers/delegated_frame_provider.h"
 #include "cc/layers/delegated_frame_resource_collection.h"
@@ skipping 115 matching lines @@
       return;
     --times_to_lose_during_commit_;
     LoseContext();
 
     times_to_fail_create_ = times_to_fail_recreate_;
     times_to_fail_recreate_ = 0;
   }
 
   void DidFailToInitializeOutputSurface() override { ++times_create_failed_; }
 
-  virtual void TearDown() override {
+  void TearDown() override {
     LayerTreeTest::TearDown();
     EXPECT_EQ(times_to_expect_create_failed_, times_create_failed_);
   }
 
   void ExpectCreateToFail() { ++times_to_expect_create_failed_; }
 
  protected:
   TestWebGraphicsContext3D* context3d_;
   int times_to_fail_create_;
   int times_to_lose_during_commit_;
@@ skipping 1630 matching lines @@
   void AfterTest() override {}
 
   bool deferred_;
 };
 
 SINGLE_AND_MULTI_THREAD_TEST_F(
     LayerTreeHostContextTestLoseAfterSendingBeginMainFrame);
 
 }  // namespace
 }  // namespace cc