Update from https://crrev.com/327068

tools/clang/plugins/tests/virtual_specifiers.cpp

 // Copyright 2014 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.
 //
 // Tests for chromium style checks for virtual/override/final specifiers on
 // virtual methods.
 
+#include <windows.h>
+
 // Purposely use macros to test that the FixIt hints don't try to remove the
 // macro body.
 #define OVERRIDE override
 #define FINAL final
 
 // Base class can only use virtual.
 class Base {
  public:
   virtual ~Base() {}
   virtual void F() = 0;
@@ skipping 54 matching lines @@
 };
 
 class PureOverride : public Base {
   void F() override = 0;
 };
 
 class PureVirtualOverride : public Base {
   virtual void F() override = 0;
 };
 
-// Finally, some simple sanity tests that overrides in the testing namespace
+// Test that the redundant virtual warning is suppressed when the virtual
+// keyword comes from a macro in a system header.
+class COMIsAwesome : public Base {
+  STDMETHOD(F)() override = 0;
+};
+
+// Some tests that overrides in the testing namespace
 // don't trigger warnings, except for testing::Test.
 namespace testing {
 
 class Test {
  public:
   virtual ~Test();
   virtual void SetUp();
 };
 
 class NotTest {
  public:
   virtual ~NotTest();
   virtual void SetUp();
 };
 
 }  // namespace
 
 class MyTest : public testing::Test {
  public:
   virtual ~MyTest();
   virtual void SetUp() override;
 };
 
 class MyNotTest : public testing::NotTest {
  public:
   virtual ~MyNotTest();
   virtual void SetUp() override;
 };