Inform disk cache of WebKit memory cache hits.

net/disk_cache/mem_backend_impl.cc

 // Copyright (c) 2011 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 "net/disk_cache/mem_backend_impl.h"
 
 #include "base/logging.h"
 #include "base/sys_info.h"
 #include "net/base/net_errors.h"
 #include "net/disk_cache/cache_util.h"
@@ skipping 170 matching lines @@
   if (OpenNextEntry(iter, next_entry))
     return net::OK;
 
   return net::ERR_FAILED;
 }
 
 void MemBackendImpl::EndEnumeration(void** iter) {
   *iter = NULL;
 }
 
+void MemBackendImpl::OnExternalCacheHit(const std::string& key) {
+  EntryMap::iterator it = entries_.find(key);
+  if (it != entries_.end()) {
+    UpdateRank(it->second);
+  }
+}
+
 bool MemBackendImpl::OpenEntry(const std::string& key, Entry** entry) {
   EntryMap::iterator it = entries_.find(key);
   if (it == entries_.end())
     return false;
 
   it->second->Open();
 
   *entry = it->second;
   return true;
 }
@@ skipping 110 matching lines @@
   if (current_size_ > max_size_)
     TrimCache(false);
 }
 
 void MemBackendImpl::SubstractStorageSize(int32 bytes) {
   current_size_ -= bytes;
   DCHECK_GE(current_size_, 0);
 }
 
 }  // namespace disk_cache