AsyncHostResolver: integrated HostCache, temporarily, until we have RR cache.

net/base/host_cache.cc

-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// 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/base/host_cache.h"
 
 #include "base/logging.h"
 #include "net/base/net_errors.h"
 
 namespace net {
 
@@ skipping 98 matching lines @@
 const HostCache::EntryMap& HostCache::entries() const {
   DCHECK(CalledOnValidThread());
   return entries_;
 }
 
 // static
 bool HostCache::CanUseEntry(const Entry* entry, const base::TimeTicks now) {
   return entry->expiration > now;
 }
 
+// static
+HostCache* HostCache::CreateDefaultCache() {
+  static const size_t kMaxHostCacheEntries = 100;
+
+  HostCache* cache = new HostCache(
+      kMaxHostCacheEntries,
+      base::TimeDelta::FromMinutes(1),
+      base::TimeDelta::FromSeconds(0));  // Disable caching of failed DNS.
+
+  return cache;
+}
+
 void HostCache::Compact(base::TimeTicks now, const Entry* pinned_entry) {
   // Clear out expired entries.
   for (EntryMap::iterator it = entries_.begin(); it != entries_.end(); ) {
     Entry* entry = (it->second).get();
     if (entry != pinned_entry && !CanUseEntry(entry, now)) {
       entries_.erase(it++);
     } else {
       ++it;
     }
   }
@@ skipping 13 matching lines @@
     } else {
       ++it;
     }
   }
 
   if (entries_.size() > max_entries_)
     DLOG(WARNING) << "Still above max entries limit";
 }
 
 }  // namespace net