[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 ae0169cf3b58b84598d8e5bbd73303ae5de0c68a..9aa5b3dab813f97aaa4850fac9eba38cd081949d 100644
--- a/net/base/host_cache.cc
+++ b/net/base/host_cache.cc
@@ -71,9 +71,9 @@ const HostCache::EntryMap& HostCache::entries() const {
 }
 
 // static
-HostCache* HostCache::CreateDefaultCache() {
+scoped_ptr<HostCache> HostCache::CreateDefaultCache() {
   static const size_t kMaxHostCacheEntries = 100;
-  return new HostCache(kMaxHostCacheEntries);
+  return make_scoped_ptr(new HostCache(kMaxHostCacheEntries));
 }
 
 }  // namespace net