ThreadRestrictions: disallow blocking IO on the UI thread

chrome/browser/browser_init.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/browser_init.h"
 
 #include <algorithm>   // For max().
 
 #include "app/l10n_util.h"
 #include "app/resource_bundle.h"
 #include "base/environment.h"
 #include "base/event_recorder.h"
 #include "base/file_path.h"
 #include "base/metrics/histogram.h"
 #include "base/path_service.h"
 #include "base/scoped_ptr.h"
 #include "base/string_number_conversions.h"
+#include "base/thread_restrictions.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/automation/automation_provider.h"
 #include "chrome/browser/automation/automation_provider_list.h"
 #include "chrome/browser/automation/chrome_frame_automation_provider.h"
 #include "chrome/browser/automation/testing_automation_provider.h"
 #include "chrome/browser/browser_list.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/browser_window.h"
 #include "chrome/browser/child_process_security_policy.h"
@@ skipping 816 matching lines @@
         continue;
       }
       const TemplateURLRef* search_url = default_provider->url();
       DCHECK(search_url->SupportsReplacement());
       std::wstring search_term = param.ToWStringHack().substr(2);
       urls.push_back(GURL(search_url->ReplaceSearchTerms(
           *default_provider, search_term,
           TemplateURLRef::NO_SUGGESTIONS_AVAILABLE, std::wstring())));
     } else {
       // This will create a file URL or a regular URL.
-      GURL url(URLFixerUpper::FixupRelativeFile(cur_dir_, param));
+      // This call can (in rare circumstances) block the UI thread.
+      // Allow it until this bug is fixed.
+      //  http://code.google.com/p/chromium/issues/detail?id=60641
+      GURL url;
+      {
+        base::ThreadRestrictions::ScopedAllowIO allow_io;
+        url = URLFixerUpper::FixupRelativeFile(cur_dir_, param);
+      }
       // Exclude dangerous schemes.
       if (url.is_valid()) {
         ChildProcessSecurityPolicy *policy =
             ChildProcessSecurityPolicy::GetInstance();
         if (policy->IsWebSafeScheme(url.scheme()) ||
             url.SchemeIs(chrome::kFileScheme) ||
             !url.spec().compare(chrome::kAboutBlankURL)) {
           urls.push_back(url);
         }
       }
@@ skipping 149 matching lines @@
   scoped_refptr<AutomationProviderClass> automation =
       new AutomationProviderClass(profile);
   automation->ConnectToChannel(channel_id);
   automation->SetExpectedTabCount(expected_tabs);
 
   AutomationProviderList* list =
       g_browser_process->InitAutomationProviderList();
   DCHECK(list);
   list->AddProvider(automation);
 }