Fix the print preview regression bug caused by r98926.

chrome/renderer/print_web_view_helper.cc

Index: chrome/renderer/print_web_view_helper.cc
diff --git a/chrome/renderer/print_web_view_helper.cc b/chrome/renderer/print_web_view_helper.cc
index 36726eee4667e71193e7de272e489219da218c46..f0d82c9fa1f6896c32bcc7d07eb966f83a8cb1df 100644
--- a/chrome/renderer/print_web_view_helper.cc
+++ b/chrome/renderer/print_web_view_helper.cc
@@ -702,19 +702,31 @@ bool PrintWebViewHelper::CreatePreviewDocument() {
   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;
 }
@@ -1470,6 +1482,10 @@ bool PrintWebViewHelper::PrintPreviewContext::IsLastPageOfPrintReadyMetafile()
   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;