Initialize bug_report_ to NULL so as make sure invalid pointer is not freed....

chrome/browser/dom_ui/bug_report_ui.cc

 // Copyright (c) 2010 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/dom_ui/bug_report_ui.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
@@ skipping 471 matching lines @@
 
 
 ////////////////////////////////////////////////////////////////////////////////
 //
 // BugReportHandler
 //
 ////////////////////////////////////////////////////////////////////////////////
 BugReportHandler::BugReportHandler(TabContents* tab)
     : tab_(tab)
     , screenshot_source_(NULL)
+    , bug_report_(NULL)
 #if defined(OS_CHROMEOS)
     , syslogs_handle_(0)
 #endif
 {
 }
 
 BugReportHandler::~BugReportHandler() {
   // Just in case we didn't send off bug_report_ to SendReport
   if (bug_report_) {
     // If we're deleting the report object, cancel feedback collection first
@@ skipping 298 matching lines @@
   BugReportUIHTMLSource* html_source =
       new BugReportUIHTMLSource(handler->Init());
   // Set up the chrome://bugreport/ source.
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       NewRunnableMethod(
           Singleton<ChromeURLDataManager>::get(),
           &ChromeURLDataManager::AddDataSource,
           make_scoped_refptr(html_source)));
 }