Use unique_ptrs in PrintPreviewDataService.

chrome/browser/printing/print_preview_data_service.cc

 // Copyright (c) 2012 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/browser/printing/print_preview_data_service.h"
 
 #include "base/macros.h"
+#include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/memory/singleton.h"
 #include "base/stl_util.h"
 #include "printing/print_job_constants.h"
 
 // PrintPreviewDataStore stores data for preview workflow and preview printing
 // workflow.
 //
 // NOTE:
 //   This class stores a list of PDFs. The list |index| is zero-based and can
 // be |printing::COMPLETE_PREVIEW_DOCUMENT_INDEX| to represent complete preview
 // document. The PDF stored at |printing::COMPLETE_PREVIEW_DOCUMENT_INDEX| is
 // optimized with font subsetting, compression, etc. PDF's stored at all other
 // indices are unoptimized.
 //
 // PrintPreviewDataStore owns the data and is responsible for freeing it when
 // either:
 //    a) There is a new data.
 //    b) When PrintPreviewDataStore is destroyed.
 //
-class PrintPreviewDataStore : public base::RefCounted<PrintPreviewDataStore> {
+class PrintPreviewDataStore {
  public:
   PrintPreviewDataStore() {}
+  ~PrintPreviewDataStore() {}
 
   // Get the preview page for the specified |index|.
   void GetPreviewDataForIndex(
       int index,
       scoped_refptr<base::RefCountedBytes>* data) const {
     if (IsInvalidIndex(index))
       return;
 
     PreviewPageDataMap::const_iterator it = page_data_map_.find(index);
     if (it != page_data_map_.end())
@@ skipping 12 matching lines @@
   // Returns the available draft page count.
   int GetAvailableDraftPageCount() const {
     int page_data_map_size = page_data_map_.size();
     if (base::ContainsKey(page_data_map_,
                           printing::COMPLETE_PREVIEW_DOCUMENT_INDEX))
       page_data_map_size--;
     return page_data_map_size;
   }
 
  private:
-  friend class base::RefCounted<PrintPreviewDataStore>;
-
   // 1:1 relationship between page index and its associated preview data.
   // Key: Page index is zero-based and can be
   // |printing::COMPLETE_PREVIEW_DOCUMENT_INDEX| to represent complete preview
   // document.
   // Value: Preview data.
   using PreviewPageDataMap =
       std::map<int, scoped_refptr<base::RefCountedBytes>>;
 
-  ~PrintPreviewDataStore() {}
-
   static bool IsInvalidIndex(int index) {
     return (index != printing::COMPLETE_PREVIEW_DOCUMENT_INDEX &&
             index < printing::FIRST_PAGE_INDEX);
   }
 
   PreviewPageDataMap page_data_map_;
 
   DISALLOW_COPY_AND_ASSIGN(PrintPreviewDataStore);
 };
 
@@ skipping 15 matching lines @@
   *data_bytes = nullptr;
   PreviewDataStoreMap::const_iterator it = data_store_map_.find(preview_ui_id);
   if (it != data_store_map_.end())
     it->second->GetPreviewDataForIndex(index, data_bytes);
 }
 
 void PrintPreviewDataService::SetDataEntry(
     int32_t preview_ui_id,
     int index,
     scoped_refptr<base::RefCountedBytes> data_bytes) {
-  if (!base::ContainsKey(data_store_map_, preview_ui_id)) {
-    data_store_map_[preview_ui_id] =
-        make_scoped_refptr(new PrintPreviewDataStore());
-  }
-
+  if (!base::ContainsKey(data_store_map_, preview_ui_id))
+    data_store_map_[preview_ui_id] = base::MakeUnique<PrintPreviewDataStore>();
   data_store_map_[preview_ui_id]->SetPreviewDataForIndex(index,
                                                          std::move(data_bytes));
 }
 
 void PrintPreviewDataService::RemoveEntry(int32_t preview_ui_id) {
   data_store_map_.erase(preview_ui_id);
 }
 
 int PrintPreviewDataService::GetAvailableDraftPageCount(
     int32_t preview_ui_id) const {
   PreviewDataStoreMap::const_iterator it = data_store_map_.find(preview_ui_id);
   return (it == data_store_map_.end()) ?
       0 : it->second->GetAvailableDraftPageCount();
 }