Be able to print items that do window.print(); window.close() (airline tix e.g.)

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 <set>
 
@@ skipping 12 matching lines @@
 class BackgroundPrintingManager
     : public base::NonThreadSafe,
       public NotificationObserver {
  public:
   BackgroundPrintingManager();
   virtual ~BackgroundPrintingManager();
 
   // Takes ownership of |content| and deletes it when |content| finishes
   // printing. This removes the TabContentsWrapper from its TabStrip and
   // hides it from the user.
-  void OwnTabContents(TabContentsWrapper* content);
+  void OwnPreviewTabContents(TabContentsWrapper* content);
+
+  // Takes ownership of |content| 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.
+  bool OwnInitiatorTabContents(TabContentsWrapper* content);
+
+  // Called when we no longer need to access the initiator tab, deletes if
+  // currently owned. Returns true when |content| was owned.
+  bool ReleaseInitiatorTabContents(TabContentsWrapper* content);
 
   // Let others iterate over the list of background printing tabs.
   std::set<TabContentsWrapper*>::const_iterator begin();
   std::set<TabContentsWrapper*>::const_iterator end();
 
   // Returns true if |printing_contents_| contains |entry|.
   bool HasTabContents(TabContentsWrapper* entry);
 
   // NotificationObserver overrides:
   virtual void Observe(int type,
                        const NotificationSource& source,
                        const NotificationDetails& details) OVERRIDE;
 
  private:
+  // Takes ownership of |content| 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.
+  void OwnTabContents(TabContentsWrapper* content,
+                      TabContentsWrapper* source_content);
+
   // The set of tabs managed by BackgroundPrintingManager.
   std::set<TabContentsWrapper*> printing_contents_;
 

[Lei Zhang, 2011/08/11 09:47:16]

If you add a second set for the initiator tabs we are holding, rather than
mixing initiator tabs and print preview tabs in |printing_contents_|, this CL
will likely be more robust and readable.

[Sheridan Rawlins, 2011/08/16 06:11:54]

Done.

   NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundPrintingManager);
 };
 
 }  // namespace printing
 
 #endif  // CHROME_BROWSER_PRINTING_BACKGROUND_PRINTING_MANAGER_H_