Fix the print preview regression bug caused by r98926.

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 684 matching lines @@
   PrintHostMsg_DidGetPreviewPageCount_Params params;
   params.page_count = print_preview_context_.total_page_count();
   params.is_modifiable = print_preview_context_.IsModifiable();
   params.document_cookie = print_pages_params_->params.document_cookie;
   params.preview_request_id = print_pages_params_->params.preview_request_id;
   params.clear_preview_data = print_preview_context_.generate_draft_pages();
   Send(new PrintHostMsg_DidGetPreviewPageCount(routing_id(), params));
   if (CheckForCancel())
     return false;
 
-  int page_number;
-  while ((page_number = print_preview_context_.GetNextPageNumber()) >= 0) {
+  while (!print_preview_context_.IsFinalPageRendered()) {

[kmadhusu, 2011/09/01 18:40:20]

GetNextPageNumber() function needs to be called when print_preview_context_ is
in "RENDERING" state. Now that we can change the print_preview_context_ to a
"DONE" state within the loop. I have changed the loop condition here.

+    int page_number = print_preview_context_.GetNextPageNumber();
+    DCHECK(page_number >= 0);
     if (!RenderPreviewPage(page_number))
       return false;
+
     if (CheckForCancel())
       return false;
+
+    // AllPagesRendered() will be called only once i.e., after rendering the

[vandebo (ex-Chrome), 2011/09/01 18:53:56]

I wouldn't include the second part of this comment, but make the first part more
focused....
// We must call PrepareFrameAndViewForPrint::FinishPrinting() (by way of
print_preview_context_.AllPagesRendered()) before calling
FinalizePrintReadyDocument() when printing a PDF because the plugin code does
not generate output until we call FinishPrinting.  We do not generate draft
pages for PDFs, so IsFinalPageRendered and IsLastPageOfPrintReadyMetafile will
be true in the same iteration of the loop.

[kmadhusu, 2011/09/01 20:07:14]

Done..

+    // required pages. This code is here because if we are previewing a PDF
+    // file, we need to invoke PrepareFrameAndViewForPrint::FinishPrinting()
+    // before calling PreviewMetafile::FinishDocument().
+    //
+    // This function call ordering is not required if we are previewing a
+    // normal html page. We can invoke PreviewMetafile::FinishDocument() as
+    // soon as the print ready doucment is available.
+    if (print_preview_context_.IsFinalPageRendered())
+      print_preview_context_.AllPagesRendered();
+
     if (print_preview_context_.IsLastPageOfPrintReadyMetafile()) {

[vandebo (ex-Chrome), 2011/09/01 18:53:56]

To help enforce the comment, you can add a DCHECK here...
DCHECK(IsModifiable() || IsFinalPageRendered()) ?

[kmadhusu, 2011/09/01 20:07:14]

Done.

-      // Finished generating preview. Finalize the document.
       if (!FinalizePrintReadyDocument())
         return false;
     }
   }
-  print_preview_context_.AllPagesRendered();
   print_preview_context_.Finished();
   return true;
 }
 
 bool PrintWebViewHelper::FinalizePrintReadyDocument() {
   DCHECK(!is_print_ready_metafile_sent_);
   print_preview_context_.FinalizePrintReadyDocument();
 
   // Get the size of the resulting metafile.
   printing::PreviewMetafile* metafile = print_preview_context_.metafile();
@@ skipping 735 matching lines @@
     return false;
   std::string mime(frame()->dataSource()->response().mimeType().utf8());
   return mime != "application/pdf";
 }
 
 bool PrintWebViewHelper::PrintPreviewContext::IsLastPageOfPrintReadyMetafile()
     const {
   return current_page_index_ == print_ready_metafile_page_count_;
 }
 
+bool  PrintWebViewHelper::PrintPreviewContext::IsFinalPageRendered() const {
+  return (size_t)current_page_index_ == pages_to_render_.size();

[vandebo (ex-Chrome), 2011/09/01 18:53:56]

static_cast<size_t>

[kmadhusu, 2011/09/01 20:07:14]

Done.

+}
+
 void PrintWebViewHelper::PrintPreviewContext::set_generate_draft_pages(
     bool generate_draft_pages) {
   generate_draft_pages_ = generate_draft_pages;
 }
 
 WebKit::WebFrame* PrintWebViewHelper::PrintPreviewContext::frame() const {
   return frame_;
 }
 
 WebKit::WebNode* PrintWebViewHelper::PrintPreviewContext::node() const {
@@ skipping 22 matching lines @@
 const gfx::Size&
 PrintWebViewHelper::PrintPreviewContext::GetPrintCanvasSize() const {
   return prep_frame_view_->GetPrintCanvasSize();
 }
 
 void PrintWebViewHelper::PrintPreviewContext::ClearContext() {
   prep_frame_view_.reset();
   metafile_.reset();
   pages_to_render_.clear();
 }