Print preview page selection should not require a rerendering of draft pages.

chrome/renderer/print_web_view_helper.h

Index: chrome/renderer/print_web_view_helper.h
diff --git a/chrome/renderer/print_web_view_helper.h b/chrome/renderer/print_web_view_helper.h
index e2bd4f67a1ae0dc32ef29507589a0e492df78007..25ff398b509c95c0a16beebf229fe91406431f41 100644
--- a/chrome/renderer/print_web_view_helper.h
+++ b/chrome/renderer/print_web_view_helper.h
@@ -6,7 +6,6 @@
 #define CHROME_RENDERER_PRINT_WEB_VIEW_HELPER_H_
 #pragma once
 
-#include <utility>
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
@@ -135,10 +134,8 @@ class PrintWebViewHelper : public RenderViewObserver,
   // Initialize the print preview document.
   bool CreatePreviewDocument();
 
-  // Continue generating the print preview. |requested_preview_page_index|
-  // specifies the browser requested preview page index. It is 1-based or
-  // |printing::INVALID_PAGE_INDEX| to continue with next page.
-  void OnContinuePreview(int requested_preview_page_index);
+  // Continue generating the print preview.
+  void OnContinuePreview();
   // Renders a print preview page. |page_number| is 0-based.
   void RenderPreviewPage(int page_number);
   // Finalize the print preview document.
@@ -292,6 +289,7 @@ class PrintWebViewHelper : public RenderViewObserver,
 
   scoped_ptr<PrintMsg_PrintPages_Params> print_pages_params_;
   bool is_preview_;
+  bool is_complete_metafile_sent_;
 
   // Used for scripted initiated printing blocking.
   base::Time last_cancelled_script_print_;
@@ -325,6 +323,9 @@ class PrintWebViewHelper : public RenderViewObserver,
     // rendering took.
     void RenderedPreviewPage(const base::TimeDelta& page_time);
 
+    // Updates the print preview context when the required pages are rendered.
+    void PreviewPagesRendered();
+
     // Finalizes the print preview document.
     void FinalizePreviewDocument();
 
@@ -342,11 +343,17 @@ class PrintWebViewHelper : public RenderViewObserver,
     bool IsReadyToRender() const;
     bool IsBusy() const;
     bool IsModifiable() const;
+    bool IsLastPageOfCompleteMetafile() const;
+    bool IsFinalPageRendered() const;
+
+    // Setters
+    void set_generate_draft_pages(bool generate_draft_pages);
 
     // Getters
     WebKit::WebFrame* frame() const;
     WebKit::WebNode* node() const;
     int total_page_count() const;
+    bool generate_draft_pages();
     printing::Metafile* metafile() const;
     const PrintMsg_Print_Params& print_params() const;
     const gfx::Size& GetPrintCanvasSize() const;
@@ -373,16 +380,17 @@ class PrintWebViewHelper : public RenderViewObserver,
     // Total page count in the renderer.
     int total_page_count_;
 
-    // Number of pages to render.
-    int actual_page_count_;
+    // List of page indices that need to be rendered.
+    std::vector<int> render_page_list_;
+
+    // Specifies the current list index.
+    int render_page_list_index_;
 
-    // The current page to render.
-    int current_page_number_;
+    // True, when draft pages needs to be generated.
+    bool generate_draft_pages_;
 
-    // |rendered_pages_| tracks which pages need to be printed as well as
-    // the page slot it should be printed in. See GetPageSlotForPage.
-    typedef std::pair<bool, int> PreviewPageInfo;
-    std::vector<PreviewPageInfo> rendered_pages_;
+    // Specifies the total number of pages in the complete metafile.
+    int complete_metafile_page_count_;
 
     base::TimeDelta document_render_time_;
     base::TimeTicks begin_time_;