Print Preview: Properly handle window.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 444 matching lines @@
     Send(new ChromeViewHostMsg_CancelPrerenderForPrinting(routing_id()));
     return;
   }
 
   if (IsScriptInitiatedPrintTooFrequent(frame))
     return;
   IncrementScriptedPrintCount();
 
   if (is_preview_enabled_) {
     print_preview_context_.InitWithFrame(frame);
-    RequestPrintPreview();
+
+    old_print_pages_params_.reset();  // Same as in RequestPrintPreview().
+    IPC::SyncMessage* msg = new PrintHostMsg_ScriptedPrintPreview(routing_id());
+    msg->EnableMessagePumping();
+    Send(msg);
   } else {
     Print(frame, WebNode());
   }
 }
 
 bool PrintWebViewHelper::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(PrintWebViewHelper, message)
     IPC_MESSAGE_HANDLER(PrintMsg_PrintPages, OnPrintPages)
     IPC_MESSAGE_HANDLER(PrintMsg_PrintForSystemDialog, OnPrintForSystemDialog)
@@ skipping 1075 matching lines @@
   DCHECK(IsRendering());
   return prep_frame_view_->GetPrintCanvasSize();
 }
 
 void PrintWebViewHelper::PrintPreviewContext::ClearContext() {
   prep_frame_view_.reset();
   metafile_.reset();
   pages_to_render_.clear();
   error_ = PREVIEW_ERROR_NONE;
 }