PrintPreview: Preview generation should not block print button.

chrome/browser/printing/print_preview_tab_controller.cc

 // 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.
 
 #include "chrome/browser/printing/print_preview_tab_controller.h"
 
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/tabs/tab_strip_model.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_list.h"
@@ skipping 140 matching lines @@
   RemoveObservers(source_tab);
 }
 
 // static
 bool PrintPreviewTabController::IsPrintPreviewTab(TabContents* tab) {
   const GURL& url = tab->GetURL();
   return (url.SchemeIs(chrome::kChromeUIScheme) &&
           url.host() == chrome::kChromeUIPrintHost);
 }
 
+void PrintPreviewTabController::EraseInitiatorTabInfo(
+    TabContents* preview_tab) {
+  PrintPreviewTabMap::iterator it = preview_tab_map_.find(preview_tab);
+  if (it == preview_tab_map_.end())
+    return;
+
+  RemoveObservers(it->second);
+  preview_tab_map_[preview_tab] = NULL;
+}
+
 TabContents* PrintPreviewTabController::GetInitiatorTab(
     TabContents* preview_tab) {
   PrintPreviewTabMap::iterator it = preview_tab_map_.find(preview_tab);
   if (it != preview_tab_map_.end())
     return preview_tab_map_[preview_tab];
   return NULL;
 }
 
 TabContents* PrintPreviewTabController::CreatePrintPreviewTab(
     TabContents* initiator_tab) {
@@ skipping 43 matching lines @@
 }
 
 void PrintPreviewTabController::RemoveObservers(TabContents* tab) {
   registrar_.Remove(this, NotificationType::TAB_CONTENTS_DESTROYED,
                     Source<TabContents>(tab));
   registrar_.Remove(this, NotificationType::NAV_ENTRY_COMMITTED,
                     Source<NavigationController>(&tab->controller()));
 }
 
 }  // namespace printing