Standardize usage of virtual/override/final specifiers.

gpu/command_buffer/service/id_manager_unittest.cc

Index: gpu/command_buffer/service/id_manager_unittest.cc
diff --git a/gpu/command_buffer/service/id_manager_unittest.cc b/gpu/command_buffer/service/id_manager_unittest.cc
index 015a44252eebd8f87a01f2d5aabe40d7b70057ff..9a6e56776528db7de6d00486aafd059e5e9ce2c4 100644
--- a/gpu/command_buffer/service/id_manager_unittest.cc
+++ b/gpu/command_buffer/service/id_manager_unittest.cc
@@ -14,11 +14,9 @@ class IdManagerTest : public testing::Test {
   }
 
  protected:
-  virtual void SetUp() {
-  }
+  void SetUp() override {}
 
-  virtual void TearDown() {
-  }
+  void TearDown() override {}
 
   IdManager manager_;
 };