Specify 'explicit' for one-parameter constructor in operations_base.h

chrome/browser/chromeos/gdata/operations_base.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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_GDATA_OPERATIONS_BASE_H_
 #define CHROME_BROWSER_CHROMEOS_GDATA_OPERATIONS_BASE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 79 matching lines @@
                               public net::URLFetcherDelegate {
  public:
   // Overridden from GDataOperationInterface.
   virtual void Start(const std::string& auth_token) OVERRIDE;
 
   // Overridden from GDataOperationInterface.
   virtual void SetReAuthenticateCallback(
       const ReAuthenticateCallback& callback) OVERRIDE;
 
  protected:
-  UrlFetchOperationBase(OperationRegistry* registry);
+  explicit UrlFetchOperationBase(OperationRegistry* registry);
   UrlFetchOperationBase(OperationRegistry* registry,
                         OperationRegistry::OperationType type,
                         const FilePath& path);
   virtual ~UrlFetchOperationBase();
 
   // Gets URL for the request.
   virtual GURL GetURL() const = 0;
   // Returns the request type. A derived class should override this method
   // for a request type other than HTTP GET.
   virtual net::URLFetcher::RequestType GetRequestType() const;
@@ skipping 112 matching lines @@
 
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate its weak pointers before any other members are destroyed.
   base::WeakPtrFactory<GetDataOperation> weak_ptr_factory_;
   DISALLOW_COPY_AND_ASSIGN(GetDataOperation);
 };
 
 }  // namespace gdata
 
 #endif  // CHROME_BROWSER_CHROMEOS_GDATA_OPERATIONS_BASE_H_