Use exactly one of final, override, and virtual

util/mach/scoped_task_suspend_test.cc

Index: util/mach/scoped_task_suspend_test.cc
diff --git a/util/mach/scoped_task_suspend_test.cc b/util/mach/scoped_task_suspend_test.cc
index c8606a0f6948696020ea0d3e6f7716ac84d6a62b..76def55f8594169a1a7c19fa05e41058afd9fd54 100644
--- a/util/mach/scoped_task_suspend_test.cc
+++ b/util/mach/scoped_task_suspend_test.cc
@@ -50,7 +50,7 @@ class ScopedTaskSuspendTest final : public MachMultiprocess {
  private:
   // MachMultiprocess:
 
-  virtual void MachMultiprocessParent() override {
+  void MachMultiprocessParent() override {
     task_t child_task = ChildTask();
 
     EXPECT_EQ(0, SuspendCount(child_task));
@@ -70,7 +70,7 @@ class ScopedTaskSuspendTest final : public MachMultiprocess {
     EXPECT_EQ(0, SuspendCount(child_task));
   }
 
-  virtual void MachMultiprocessChild() override {
+  void MachMultiprocessChild() override {
     CheckedReadFDAtEOF(ReadPipeFD());
   }