Print Preview: Hold on to tabs that do window.print(); window.close() until print preview finishes.

chrome/browser/printing/background_printing_manager.h

 // 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.
 
 #ifndef CHROME_BROWSER_PRINTING_BACKGROUND_PRINTING_MANAGER_H_
 #define CHROME_BROWSER_PRINTING_BACKGROUND_PRINTING_MANAGER_H_
 #pragma once
 
+#include <map>
 #include <set>
 
 #include "base/compiler_specific.h"
 #include "base/threading/non_thread_safe.h"
 #include "content/common/notification_observer.h"
 #include "content/common/notification_registrar.h"
 
+class RenderProcessHost;
 class TabContentsWrapper;
 
 namespace printing {
 
 // Manages hidden tabs that prints documents in the background.
 // The hidden tabs are no longer part of any Browser / TabStripModel.
 // They get deleted when the tab finishes printing.
 class BackgroundPrintingManager : public base::NonThreadSafe,
                                   public NotificationObserver {
  public:
   typedef std::set<TabContentsWrapper*> TabContentsWrapperSet;
 
   BackgroundPrintingManager();
   virtual ~BackgroundPrintingManager();
 
   // Takes ownership of |preview_tab| and deletes it when |preview_tab| finishes
   // printing. This removes the TabContentsWrapper from its TabStrip and
   // hides it from the user.
   void OwnPrintPreviewTab(TabContentsWrapper* preview_tab);
 
+  // Takes ownership of |initiator_tab| and deletes it when its preview tab is
+  // destroyed by either being canceled, closed or finishing printing. This
+  // removes the TabContentsWrapper from its TabStrip and hides it from the
+  // user. Returns true if content has an associated print preview tab,
+  // otherwise, returns false and does not take ownership of |initiator_tab|.
+  bool OwnInitiatorTab(TabContentsWrapper* initiator_tab);
+
   // Let others iterate over the list of background printing tabs.
   TabContentsWrapperSet::const_iterator begin();
   TabContentsWrapperSet::const_iterator end();
 
   // Returns true if |printing_tabs_| contains |preview_tab|.
   bool HasPrintPreviewTab(TabContentsWrapper* preview_tab);
 
   // NotificationObserver overrides:
   virtual void Observe(int type,
                        const NotificationSource& source,
                        const NotificationDetails& details) OVERRIDE;
 
  private:
+  typedef std::map<TabContentsWrapper*, TabContentsWrapper*>
+      TabContentsWrapperMap;
+
+  // Notifications handlers.
+  void OnRendererProcessClosed(RenderProcessHost* rph);
+  void OnPrintJobReleased(TabContentsWrapper* preview_tab);
+  void OnTabContentsDestroyed(TabContentsWrapper* preview_tab);
+
+  // Removes |tab| from its tab strip.
+  void RemoveFromTabStrip(TabContentsWrapper* tab);
+
   // The set of print preview tabs managed by BackgroundPrintingManager.
   TabContentsWrapperSet printing_tabs_;
 
+  // 1:1 mapping between an initiator tab managed by BackgroundPrintingManager
+  // and its associated print preview tab. The print preview tab need not be in
+  // |printing_tabs_|.
+  // Key: print preview tab.
+  // Value: initiator tab.
+  TabContentsWrapperMap map_;
+
   NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundPrintingManager);
 };
 
 }  // namespace printing
 
 #endif  // CHROME_BROWSER_PRINTING_BACKGROUND_PRINTING_MANAGER_H_