Browser should not crash when a page showing a quota infobar is closed/reloaded

chrome/browser/chrome_quota_permission_context.cc

 // Copyright (c) 2011 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/chrome_quota_permission_context.h"
 
 #include <string>
 
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ skipping 30 matching lines @@
       const std::string& display_languages,
       PermissionCallback* callback)
       : ConfirmInfoBarDelegate(tab_contents),
         context_(context),
         origin_url_(origin_url),
         display_languages_(display_languages),
         requested_quota_(requested_quota),
         callback_(callback) {}
 
  private:
-  virtual ~RequestQuotaInfoBarDelegate() {
-    // Make sure we've dispatched the callback.
-    DCHECK(!callback_.get());

[michaeln, 2011/08/15 17:51:05]

The fact that we're tripping on this DCHECK indicates something wasn't working
as expected. Is it really ok to just remove the check, or is more needed to
handle this case?

- is it ok to not run the callback, is the caller left hanging?
- is it ok to delete the calback on the UI thread instead of the IO thread?

Would it be better to call...

context_->DispatchCallbackOnIOThread(
   callback_.release(),    
   QuotaPermissionContext::kResponseCancelled);

... at this point?

-  }
+  virtual ~RequestQuotaInfoBarDelegate() {}
 
   virtual bool ShouldExpire(
       const content::LoadCommittedDetails& details)
       const OVERRIDE {
     return false;
   }
   virtual string16 GetMessageText() const OVERRIDE;
   virtual void InfoBarDismissed() OVERRIDE;
   virtual bool Accept() OVERRIDE;
   virtual bool Cancel() OVERRIDE;
@@ skipping 92 matching lines @@
   if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
     BrowserThread::PostTask(
         BrowserThread::IO, FROM_HERE,
         NewRunnableMethod(
             this, &ChromeQuotaPermissionContext::DispatchCallbackOnIOThread,
             callback.release(), response));
     return;
   }
   callback->Run(response);
 }