DCHECK for a valid error callback callback in GetIsPinnedToTaskbarState

chrome/browser/shell_integration_win.cc

 // 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.
 
 #include "chrome/browser/shell_integration_win.h"
 
 #include <windows.h>
 #include <shlwapi.h>
 #include <shobjidl.h>
 #include <propkey.h>  // Needs to come after shobjidl.h.
@@ skipping 469 matching lines @@
   new IsPinnedToTaskbarHelper(error_callback, result_callback);
 }
 
 IsPinnedToTaskbarHelper::IsPinnedToTaskbarHelper(
     const ErrorCallback& error_callback,
     const ResultCallback& result_callback)
     : shell_handler_(
           l10n_util::GetStringUTF16(IDS_UTILITY_PROCESS_SHELL_HANDLER_NAME)),
       error_callback_(error_callback),
       result_callback_(result_callback) {
+  DCHECK(error_callback_);
+  DCHECK(result_callback_);
+
   // |shell_handler_| owns the callbacks and is guaranteed to be destroyed
   // before |this|, therefore making base::Unretained() safe to use.
   shell_handler_.set_error_callback(base::Bind(
       &IsPinnedToTaskbarHelper::OnConnectionError, base::Unretained(this)));
   shell_handler_.set_disable_sandbox();
   shell_handler_.Start();
 
   shell_handler_.service()->IsPinnedToTaskbar(
       base::Bind(&IsPinnedToTaskbarHelper::OnIsPinnedToTaskbarResult,
                  base::Unretained(this)));
@@ skipping 391 matching lines @@
     if (base::PathExists(shortcut))
       return shortcut;
   }
 
   return base::FilePath();
 }
 
 }  // namespace win
 
 }  // namespace shell_integration