chromeos: Fix StartupBrowserCreatorImpl::Launch crash.

chrome/browser/ui/startup/startup_browser_creator_impl.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/ui/startup/startup_browser_creator_impl.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/compiler_specific.h"
 #include "base/environment.h"
@@ skipping 54 matching lines @@
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_result_codes.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_version_info.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/installer/util/browser_distribution.h"
 #include "content/public/browser/child_process_security_policy.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_view.h"
 #include "grit/locale_settings.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 
 #if defined(OS_MACOSX)
 #include "base/mac/mac_util.h"
 #include "chrome/browser/ui/cocoa/keystone_infobar_delegate.h"
 #endif
@@ skipping 133 matching lines @@
     }
   }
   for (size_t i = 0; i < autolaunch_tabs.size(); ++i) {
     if (extension_service->IsInstalledApp(autolaunch_tabs.at(i).url)) {
       AppLauncherHandler::RecordAppLaunchType(
           extension_misc::APP_LAUNCH_AUTOLAUNCH);
     }
   }
 }
 
+class WebContentsCloseObserver : public content::NotificationObserver {
+ public:
+  WebContentsCloseObserver() : contents_(NULL) {}
+  virtual ~WebContentsCloseObserver() {}
+
+  void SetContents(content::WebContents* contents) {
+    DCHECK(!contents_);
+    contents_ = contents;
+
+    registrar_.Add(this,
+                   content::NOTIFICATION_WEB_CONTENTS_DESTROYED,
+                   content::Source<content::WebContents>(contents_));
+  }
+
+  content::WebContents* contents() { return contents_; }
+
+ private:
+  // content::NotificationObserver overrides:
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE {
+    DCHECK_EQ(type, content::NOTIFICATION_WEB_CONTENTS_DESTROYED);
+    contents_ = NULL;
+  }
+
+  content::WebContents* contents_;
+  content::NotificationRegistrar registrar_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebContentsCloseObserver);
+};
+
 }  // namespace
 
 StartupBrowserCreatorImpl::StartupBrowserCreatorImpl(
     const FilePath& cur_dir,
     const CommandLine& command_line,
     chrome::startup::IsFirstRun is_first_run)
     : cur_dir_(cur_dir),
       command_line_(command_line),
       profile_(NULL),
       browser_creator_(NULL),
@@ skipping 63 matching lines @@
       !browser_defaults::kAppRestoreSession) {
     RecordLaunchModeHistogram(LM_AS_WEBAPP);
   } else {
     RecordLaunchModeHistogram(urls_to_open.empty() ?
                               LM_TO_BE_DECIDED : LM_WITH_URLS);
 
     // Notify user if the Preferences backup is invalid or changes to settings
     // affecting browser startup have been detected.
     CheckPreferencesBackup(profile);
 
+    // Watch for |app_contents| closing since ProcessLaunchURLs might run a
+    // synchronous session restore which has a nested message loop and could
+    // close |app_contents|.
+    WebContentsCloseObserver app_contents_observer;
+    if (browser_defaults::kAppRestoreSession && app_contents)
+      app_contents_observer.SetContents(app_contents);
+
     ProcessLaunchURLs(process_startup, urls_to_open);
 
     // If this is an app launch, but we didn't open an app window, it may
     // be an app tab.
     OpenApplicationTab(profile);
 
     // In case of app mode + session restore we want to focus that app.
-    if (browser_defaults::kAppRestoreSession && app_contents)
-      app_contents->GetView()->SetInitialFocus();
+    if (app_contents_observer.contents())
+      app_contents_observer.contents()->GetView()->SetInitialFocus();
 
     if (process_startup) {
       if (browser_defaults::kOSSupportsOtherBrowsers &&
           !command_line_.HasSwitch(switches::kNoDefaultBrowserCheck)) {
         if (!chrome::ShowAutolaunchPrompt(profile))
           chrome::ShowDefaultBrowserPrompt(profile);
       }
 #if defined(OS_MACOSX)
       // Check whether the auto-update system needs to be promoted from user
       // to system.
@@ skipping 531 matching lines @@
         // New:
         prefs->GetString(prefs::kHomePage),
         prefs->GetBoolean(prefs::kHomePageIsNewTabPage),
         prefs->GetBoolean(prefs::kShowHomeButton),
         // Backup:
         backup_homepage,
         backup_homepage_is_ntp,
         backup_show_home_button));
   }
 }