Print Preview: Display a throbber when the user requests the system print

chrome/renderer/print_web_view_helper.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/renderer/print_web_view_helper.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 652 matching lines @@
   params.routing_id = render_view()->routing_id();
   // host_window_ may be NULL at this point if the current window is a
   // popup and the print() command has been issued from the parent. The
   // receiver of this message has to deal with this.
   params.host_window_id = render_view()->host_window();
   params.cookie = print_pages_params_->params.document_cookie;
   params.has_selection = frame->hasSelection();
   params.expected_pages_count = expected_pages_count;
   params.use_overlays = use_browser_overlays;
 
+  Send(new PrintHostMsg_DidShowPrintDialog(routing_id()));
+
   print_pages_params_.reset();
   IPC::SyncMessage* msg =
       new PrintHostMsg_ScriptedPrint(routing_id(), params, &print_settings);
   msg->EnableMessagePumping();
   Send(msg);
   print_pages_params_.reset(new PrintMsg_PrintPages_Params(print_settings));
   return (print_settings.params.dpi && print_settings.params.document_cookie);
 }
 
 bool PrintWebViewHelper::RenderPagesForPrint(WebKit::WebFrame* frame,
@@ skipping 114 matching lines @@
 
   render_view()->runModalAlertDialog(
       web_view->mainFrame(),
       l10n_util::GetStringUTF16(IDS_PRINT_SPOOL_FAILED_ERROR_TEXT));
 }
 
 void PrintWebViewHelper::RequestPrintPreview() {
   old_print_pages_params_.reset();
   Send(new PrintHostMsg_RequestPrintPreview(routing_id()));
 }