diff --git a/common/prefs_unittest.cc b/common/prefs_unittest.cc
index a5f46e5..cef6d44 100644
--- a/common/prefs_unittest.cc
+++ b/common/prefs_unittest.cc
@@ -507,8 +507,8 @@
 
 class MockPrefsObserver : public PrefsInterface::ObserverInterface {
  public:
-  MOCK_METHOD1(OnPrefSet, void(const string&));
-  MOCK_METHOD1(OnPrefDeleted, void(const string& key));
+  MOCK_METHOD1(OnPrefSet, void(std::string_view));
+  MOCK_METHOD1(OnPrefDeleted, void(std::string_view));
 };
 
 TEST_F(PrefsTest, ObserversCalled) {