Backing out bug 407080 to investigate breakage of mochitest test_bug396024.html

layout/printing/nsPrintEngine.cpp

@@ -729,20 +729,6 @@ nsPrintEngine::PrintPreview(nsIPrintSettings* aPrintSettings,
                                  nsIDOMWindow *aChildDOMWin, 
                                  nsIWebProgressListener* aWebProgressListener)
 {
-  // Get the DocShell and see if it is busy
-  // (We can't Print Preview this document if it is still busy)
-  nsCOMPtr<nsIDocShell> docShell(do_QueryInterface(mContainer));
-  NS_ASSERTION(docShell, "This has to be a docshell");
-
-  PRUint32 busyFlags = nsIDocShell::BUSY_FLAGS_NONE;
-  if (NS_FAILED(docShell->GetBusyFlags(&busyFlags)) ||
-      busyFlags != nsIDocShell::BUSY_FLAGS_NONE) {
-    CloseProgressDialog(aWebProgressListener);
-    ShowPrintErrorDialog(NS_ERROR_GFX_PRINTER_DOC_IS_BUSY_PP, PR_FALSE);
-    return NS_ERROR_FAILURE;
-  }
-
-  // Document is not busy -- go ahead with the Print Preview
   return CommonPrint(PR_TRUE, aPrintSettings, aWebProgressListener);
 }