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>
 
 #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 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 |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,
+  // otherwise, returns false and does not take ownership of |content|.
+  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();
+  TabContentsWrapperSet::const_iterator begin();
+  TabContentsWrapperSet::const_iterator end();
 
   // Returns true if |printing_contents_| contains |entry|.
   bool HasTabContents(TabContentsWrapper* entry);

[Lei Zhang, 2011/08/26 10:01:54]

Probably want to rename this to HasPreviewTabContents.

[Sheridan Rawlins, 2011/08/26 23:45:39]

Done.

 
   // NotificationObserver overrides:
   virtual void Observe(int type,
                        const NotificationSource& source,
                        const NotificationDetails& details) OVERRIDE;
 
  private:
+
+  // Called when the preview tab is going away to release the corresponding
+  // initiator tab. Returns true when the initiator content was owned.
+  bool ReleaseInitiatorForPreviewTabContents(
+      TabContentsWrapper* preview_content);
+
+  // Takes ownership of |content| in |wrapper_set| and deletes it when
+  // |source_content| 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,
+                      TabContentsWrapperSet* wrapper_set);
+
   // The set of tabs managed by BackgroundPrintingManager.
-  std::set<TabContentsWrapper*> printing_contents_;
+  TabContentsWrapperSet printing_contents_;
+
+  // The set of tabs managed by BackgroundPrintingManager.

[Lei Zhang, 2011/08/26 10:01:54]

update comment

[Sheridan Rawlins, 2011/08/26 23:45:39]

Done.

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