PrintPreview: Preview generation should not block print button.

chrome/browser/printing/print_preview_message_handler.cc

Index: chrome/browser/printing/print_preview_message_handler.cc
diff --git a/chrome/browser/printing/print_preview_message_handler.cc b/chrome/browser/printing/print_preview_message_handler.cc
index d293d6f1d6e2829f2f43e1e7e3964fb66a627179..f56bb62475d7267a37d573ed5699977f5d0611ef 100644
--- a/chrome/browser/printing/print_preview_message_handler.cc
+++ b/chrome/browser/printing/print_preview_message_handler.cc
@@ -6,6 +6,7 @@
 
 #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"
@@ -114,7 +115,22 @@ void PrintPreviewMessageHandler::OnPrintPreviewFailed(int document_cookie) {
   // 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.
+    RenderViewHost* rvh = tab_contents()->render_view_host();
+    rvh->Send(new PrintMsg_PrintingDone(rvh->routing_id(), false));

[Lei Zhang, 2011/06/09 22:39:07]

So you said this is to tell PWVH to cleanup after itself, because
PrintMsg_PrintingDone will eventually lead to PWVH::DidFinishPrinting().

However, the only case where you can get here in the first place is if
PWVH::DidFinishPrinting() sends PrintHostMsg_PrintPreviewFailed, so it would
have already done the cleanup that you want it to do here.

[kmadhusu, 2011/06/09 23:55:48]

Removed the msg. I will handle the error case in my next CL.

+    delete print_preview_tab;

[Lei Zhang, 2011/06/09 22:39:07]

Can you delete |wrapper| instead? In a separate CL, sky was worried about us
deleting the TabContent and leaving an invalid wrapper.

[kmadhusu, 2011/06/09 23:55:48]

Done

+    return;
+  } else {
+    PrintPreviewUI* print_preview_ui =
+      static_cast<PrintPreviewUI*>(print_preview_tab->web_ui());
+    print_preview_ui->CallJavascriptFunction("printPreviewFailed");
+  }
 }
 
 bool PrintPreviewMessageHandler::OnMessageReceived(