Update {virtual,override} to follow C++11 style in components.

components/policy/core/common/async_policy_provider_unittest.cc

Index: components/policy/core/common/async_policy_provider_unittest.cc
diff --git a/components/policy/core/common/async_policy_provider_unittest.cc b/components/policy/core/common/async_policy_provider_unittest.cc
index 6219346ab370c93993c49a076f36ffbdef8de369..9dc54f528b9d608acd83dbae7f6bc2606ab43f02 100644
--- a/components/policy/core/common/async_policy_provider_unittest.cc
+++ b/components/policy/core/common/async_policy_provider_unittest.cc
@@ -41,13 +41,13 @@ class MockPolicyLoader : public AsyncPolicyLoader {
  public:
   explicit MockPolicyLoader(
       scoped_refptr<base::SequencedTaskRunner> task_runner);
-  virtual ~MockPolicyLoader();
+  ~MockPolicyLoader() override;
 
   // Load() returns a scoped_ptr<PolicyBundle> but it can't be mocked because
   // scoped_ptr is moveable but not copyable. This override forwards the
   // call to MockLoad() which returns a PolicyBundle*, and returns a copy
   // wrapped in a passed scoped_ptr.
-  virtual scoped_ptr<PolicyBundle> Load() override;
+  scoped_ptr<PolicyBundle> Load() override;
 
   MOCK_METHOD0(MockLoad, const PolicyBundle*());
   MOCK_METHOD0(InitOnBackgroundThread, void());