Refactor: Remove HostResolver::GetAsHostResolverImpl()

The only remaining place this was used was to start the IPv6 probe. 

That's moved to a function on the interface which is a no-op for most resolvers.


Review URL: http://codereview.chromium.org/8364009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@106753 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/net/base/host_resolver_impl.cc b/net/base/host_resolver_impl.cc
index 43aaacc..c4002e6 100644
--- a/net/base/host_resolver_impl.cc
+++ b/net/base/host_resolver_impl.cc
@@ -1117,13 +1117,6 @@
     delete job_pools_[i];
 }
 
-void HostResolverImpl::ProbeIPv6Support() {
-  DCHECK(CalledOnValidThread());
-  DCHECK(!ipv6_probe_monitoring_);
-  ipv6_probe_monitoring_ = true;
-  OnIPAddressChanged();  // Give initial setup call.
-}
-
 void HostResolverImpl::SetPoolConstraints(JobPoolIndex pool_index,
                                           size_t max_outstanding_jobs,
                                           size_t max_pending_requests) {
@@ -1296,8 +1289,11 @@
   return default_address_family_;
 }
 
-HostResolverImpl* HostResolverImpl::GetAsHostResolverImpl() {
-  return this;
+void HostResolverImpl::ProbeIPv6Support() {
+  DCHECK(CalledOnValidThread());
+  DCHECK(!ipv6_probe_monitoring_);
+  ipv6_probe_monitoring_ = true;
+  OnIPAddressChanged();  // Give initial setup call.
 }
 
 HostCache* HostResolverImpl::GetHostCache() {