[net] Change factory methods for HostResolver and HostCache to return a scoped_ptr

net/base/host_cache.cc

Index: net/base/host_cache.cc
diff --git a/net/base/host_cache.cc b/net/base/host_cache.cc
index f94b6869d76bf4e0b1f76f6117ded61774c93c9f..1f4719a3a67bd266586dfbab4468a9e6b798d2ae 100644
--- a/net/base/host_cache.cc
+++ b/net/base/host_cache.cc
@@ -71,7 +71,7 @@ const HostCache::EntryMap& HostCache::entries() const {
 }
 
 // static
-HostCache* HostCache::CreateDefaultCache() {
+scoped_ptr<HostCache> HostCache::CreateDefaultCache() {
 #if defined(OS_CHROMEOS)
   // Increase HostCache size for the duration of the async DNS field trial.
   // http://crbug.com/143454
@@ -80,7 +80,7 @@ HostCache* HostCache::CreateDefaultCache() {
 #else
   static const size_t kMaxHostCacheEntries = 100;
 #endif
-  return new HostCache(kMaxHostCacheEntries);
+  return make_scoped_ptr(new HostCache(kMaxHostCacheEntries));
 }
 
 }  // namespace net