Reland of Implement cache counting for the simple and memory backends - with fixed test.

net/disk_cache/simple/simple_backend_impl.h

 // Copyright (c) 2013 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.
 
 #ifndef NET_DISK_CACHE_SIMPLE_SIMPLE_BACKEND_IMPL_H_
 #define NET_DISK_CACHE_SIMPLE_SIMPLE_BACKEND_IMPL_H_
 
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 122 matching lines @@
   void InitializeIndex(const CompletionCallback& callback,
                        const DiskStatResult& result);
 
   // Dooms all entries previously accessed between |initial_time| and
   // |end_time|. Invoked when the index is ready.
   void IndexReadyForDoom(base::Time initial_time,
                          base::Time end_time,
                          const CompletionCallback& callback,
                          int result);
 
+  // Calculates the size of the entire cache. Invoked when the index is ready.
+  void IndexReadyForSizeCalculation(const CompletionCallback& callback,
+                                    int result);
+
   // Try to create the directory if it doesn't exist. This must run on the IO
   // thread.
   static DiskStatResult InitCacheStructureOnDisk(const base::FilePath& path,
                                                  uint64 suggested_max_size);
 
   // Searches |active_entries_| for the entry corresponding to |key|. If found,
   // returns the found entry. Otherwise, creates a new entry and returns that.
   scoped_refptr<SimpleEntryImpl> CreateOrFindActiveEntry(
       uint64 entry_hash,
       const std::string& key);
@@ skipping 51 matching lines @@
   // is complete. The base::Closure map target is used to store deferred
   // operations to be run at the completion of the Doom.
   base::hash_map<uint64, std::vector<base::Closure> > entries_pending_doom_;
 
   net::NetLog* const net_log_;
 };
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_SIMPLE_SIMPLE_BACKEND_IMPL_H_