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

chrome/browser/printing/print_preview_data_service.cc

Index: chrome/browser/printing/print_preview_data_service.cc
diff --git a/chrome/browser/printing/print_preview_data_service.cc b/chrome/browser/printing/print_preview_data_service.cc
index 53ba36f81e00e1d493b537171e8a319568e3f184..cd692162ecf444c5396612b7b1f8391bf4a82668 100644
--- a/chrome/browser/printing/print_preview_data_service.cc
+++ b/chrome/browser/printing/print_preview_data_service.cc
@@ -49,6 +49,15 @@ class PrintPreviewDataStore : public base::RefCounted<PrintPreviewDataStore> {
     page_data_map_[index] = const_cast<RefCountedBytes*>(data);
   }
 
+  // Returns true if the draft pages is available.
+  bool IsDraftPagesAvailable(int draft_page_count) {
+    int page_data_map_size = page_data_map_.size();
+    return (page_data_map_size > draft_page_count ||
+            (page_data_map_size == draft_page_count &&
+             (page_data_map_.find(printing::COMPLETE_PREVIEW_DOCUMENT_INDEX) ==
+              page_data_map_.end())));
+  }
+
  private:
   friend class base::RefCounted<PrintPreviewDataStore>;
 
@@ -105,3 +114,13 @@ void PrintPreviewDataService::RemoveEntry(
   if (it != data_store_map_.end())
     data_store_map_.erase(it);
 }
+
+bool PrintPreviewDataService::IsDraftPagesAvailable(
+    const std::string& preview_ui_addr_str,
+    int draft_page_count) {
+  if (data_store_map_.find(preview_ui_addr_str) != data_store_map_.end()) {
+    return data_store_map_[preview_ui_addr_str]->IsDraftPagesAvailable(
+        draft_page_count);
+  }
+  return false;
+}