RefCounted types should not have public destructors

chrome/browser/managed_mode_unittest.cc

Index: chrome/browser/managed_mode_unittest.cc
diff --git a/chrome/browser/managed_mode_unittest.cc b/chrome/browser/managed_mode_unittest.cc
index 712dcc7f8b063d05e9737abb3dfc2a946fdd4b93..7beee9fac9ea232ae49938bd5d57d5fabb189ba9 100644
--- a/chrome/browser/managed_mode_unittest.cc
+++ b/chrome/browser/managed_mode_unittest.cc
@@ -94,7 +94,6 @@ class MockCallback : public base::RefCountedThreadSafe<MockCallback> {
   explicit MockCallback(FakeManagedMode* managed_mode)
       : managed_mode_(managed_mode) {
   }
-  virtual ~MockCallback() {}
 
   void CheckManagedMode(bool success) {
     EXPECT_EQ(managed_mode_->IsInManagedModeImpl(), success);
@@ -103,7 +102,12 @@ class MockCallback : public base::RefCountedThreadSafe<MockCallback> {
 
   MOCK_METHOD1(DidEnterManagedMode, void(bool));
 
+ protected:
+  virtual ~MockCallback() {}
+
  private:
+  friend class base::RefCountedThreadSafe<MockCallback>;
+
   FakeManagedMode* managed_mode_;
 
   DISALLOW_COPY_AND_ASSIGN(MockCallback);