Use exactly one of final, override, and virtual

util/mach/exc_server_variants_test.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 921 matching lines @@
       EXPECT_EQ(0u, *new_state_count);
       EXPECT_EQ(NULL, new_state);
     }
 
     return ExcServerSuccessfulReturnValue(behavior, false);
   }
 
  private:
   // MachMultiprocess:
 
-  virtual void MachMultiprocessParent() override {
+  void MachMultiprocessParent() override {
     kern_return_t kr = MachMessageServer::Run(this,
                                               LocalPort(),
                                               MACH_MSG_OPTION_NONE,
                                               MachMessageServer::kOneShot,
                                               MachMessageServer::kBlocking,
                                               0);
     EXPECT_EQ(KERN_SUCCESS, kr)
         << MachErrorMessage(kr, "MachMessageServer::Run");
 
     EXPECT_TRUE(handled_);
   }
 
-  virtual void MachMultiprocessChild() override {
+  void MachMultiprocessChild() override {
     // Set the parent as the exception handler for EXC_CRASH.
     kern_return_t kr = task_set_exception_ports(
         mach_task_self(), EXC_MASK_CRASH, RemotePort(), behavior_, flavor_);
     ASSERT_EQ(KERN_SUCCESS, kr)
         << MachErrorMessage(kr, "task_set_exception_ports");
 
     // Now crash.
     __builtin_trap();
   }
 
@@ skipping 201 matching lines @@
 
     EXPECT_EQ(test_data.kr,
               ExcServerSuccessfulReturnValue(test_data.behavior,
                                              test_data.set_thread_state));
   }
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace crashpad