PrintPreview: Preview generation should not block print button.

chrome/browser/printing/print_preview_message_handler.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_message_handler.h"
 
 #include "base/memory/ref_counted.h"
 #include "chrome/browser/browser_process.h"
+#include "chrome/browser/printing/background_printing_manager.h"
 #include "chrome/browser/printing/print_job_manager.h"
 #include "chrome/browser/printing/print_preview_tab_controller.h"
 #include "chrome/browser/printing/print_view_manager.h"
 #include "chrome/browser/printing/printer_query.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "chrome/browser/ui/webui/print_preview_handler.h"
 #include "chrome/browser/ui/webui/print_preview_ui.h"
 #include "chrome/common/print_messages.h"
 #include "content/browser/browser_thread.h"
 #include "content/browser/renderer_host/render_view_host.h"
@@ skipping 88 matching lines @@
 
 void PrintPreviewMessageHandler::OnPrintPreviewFailed(int document_cookie) {
   // Always need to stop the worker.
   StopWorker(document_cookie);
 
   // Inform the print preview tab of the failure.
   TabContents* print_preview_tab = GetPrintPreviewTab();
   // User might have closed it already.
   if (!print_preview_tab)
     return;
-  print_preview_tab->web_ui()->CallJavascriptFunction("printPreviewFailed");
+
+  TabContentsWrapper* wrapper =
+      TabContentsWrapper::GetCurrentWrapperForContents(print_preview_tab);
+
+  if (g_browser_process->background_printing_manager()->
+          HasTabContents(wrapper)) {
+    // Preview tab was hidden to serve the print request.
+    delete wrapper;
+  } else {
+    PrintPreviewUI* print_preview_ui =
+      static_cast<PrintPreviewUI*>(print_preview_tab->web_ui());
+    print_preview_ui->CallJavascriptFunction("printPreviewFailed");
+  }
 }
 
 bool PrintPreviewMessageHandler::OnMessageReceived(
     const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(PrintPreviewMessageHandler, message)
     IPC_MESSAGE_HANDLER(PrintHostMsg_RequestPrintPreview,
                         OnRequestPrintPreview)
     IPC_MESSAGE_HANDLER(PrintHostMsg_PagesReadyForPreview,
                         OnPagesReadyForPreview)
     IPC_MESSAGE_HANDLER(PrintHostMsg_PrintPreviewFailed,
                         OnPrintPreviewFailed)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
 void PrintPreviewMessageHandler::DidStartLoading() {
   if (tab_contents()->delegate() &&
       printing::PrintPreviewTabController::IsPrintPreviewTab(tab_contents())) {
     tab_contents()->SetContentRestrictions(CONTENT_RESTRICTION_PRINT);
   }
 }
 
 }  // namespace printing