RefCounted types should not have public destructors, delegate cleanup

chrome/browser/cancelable_request.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // CancelableRequestProviders and Consumers work together to make requests that
 // execute on a background thread in the provider and return data to the
 // consumer. These classes collaborate to keep a list of open requests and to
 // make sure that requests do not outlive either of the objects involved in the
 // transaction.
 //
@@ skipping 104 matching lines @@
 //
 // It is intended that providers inherit from this class to provide the
 // necessary functionality.
 
 class CancelableRequestProvider {
  public:
   // Identifies a specific request from this provider.
   typedef int Handle;
 
   CancelableRequestProvider();
-  virtual ~CancelableRequestProvider();
 
   // Called by the enduser of the request to cancel it. This MUST be called on
   // the same thread that originally issued the request (which is also the same
   // thread that would have received the callback if it was not canceled).
   // handle must be for a valid pending (not yet complete or cancelled) request.
   void CancelRequest(Handle handle);
 
  protected:
+  virtual ~CancelableRequestProvider();
+
   // Adds a new request and initializes it. This is called by a derived class
   // to add a new request. The request's Init() will be called (which is why
   // the consumer is required. The handle to the new request is returned.
   Handle AddRequest(CancelableRequestBase* request,
                     CancelableRequestConsumerBase* consumer);
 
   // Called by the CancelableRequest when the request has executed. It will
   // be removed from the list of pending requests (as opposed to canceling,
   // which will also set some state on the request).
   void RequestCompleted(Handle handle);
@@ skipping 863 matching lines @@
   }
 
   // The value.
   Type value;
 
  protected:
   virtual ~CancelableRequest1() {}
 };
 
 #endif  // CHROME_BROWSER_CANCELABLE_REQUEST_H_