[net] Fix parsing of HostCacheSize field trial group name.

net/base/host_cache.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 "net/base/host_cache.h"
 
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/string_number_conversions.h"
@@ skipping 68 matching lines @@
 const HostCache::EntryMap& HostCache::entries() const {
   DCHECK(CalledOnValidThread());
   return entries_;
 }
 
 // static
 scoped_ptr<HostCache> HostCache::CreateDefaultCache() {
   // Cache capacity is determined by the field trial.
   const size_t kSaneMaxEntries = 1 << 20;
   size_t max_entries = 0;
-  if (!base::StringToSizeT(base::FieldTrialList::FindFullName("HostCacheSize"),
-                           &max_entries) || max_entries > kSaneMaxEntries) {
+  base::StringToSizeT(base::FieldTrialList::FindFullName("HostCacheSize"),
+                      &max_entries);
+  if ((max_entries == 0) || (max_entries > kSaneMaxEntries))
     max_entries = 100;
-  }
   return make_scoped_ptr(new HostCache(max_entries));
 }
 
 void HostCache::EvictionHandler::Handle(
     const Key& key,
     const Entry& entry,
     const base::TimeTicks& expiration,
     const base::TimeTicks& now,
     bool on_get) const {
   if (on_get) {
     DCHECK(now >= expiration);
     UMA_HISTOGRAM_CUSTOM_TIMES("DNS.CacheExpiredOnGet", now - expiration,
         base::TimeDelta::FromSeconds(1), base::TimeDelta::FromDays(1), 100);
     return;
   }
   if (expiration > now) {
     UMA_HISTOGRAM_CUSTOM_TIMES("DNS.CacheEvicted", expiration - now,
         base::TimeDelta::FromSeconds(1), base::TimeDelta::FromDays(1), 100);
   } else {
     UMA_HISTOGRAM_CUSTOM_TIMES("DNS.CacheExpired", now - expiration,
         base::TimeDelta::FromSeconds(1), base::TimeDelta::FromDays(1), 100);
   }
 }
 
 }  // namespace net