Flush socket pools and SPDY session pool properly on explicit requests and network changes.

net/base/host_resolver_impl.h

Index: net/base/host_resolver_impl.h
diff --git a/net/base/host_resolver_impl.h b/net/base/host_resolver_impl.h
index 9652072437bceec304d0424d80b1a1ec42294af6..1a87dfe439258cd5a78d27129ee5a6985465267d 100644
--- a/net/base/host_resolver_impl.h
+++ b/net/base/host_resolver_impl.h
@@ -47,8 +47,7 @@ namespace net {
 //
 // Requests are ordered in the queue based on their priority.
 
-class HostResolverImpl : public HostResolver,
-                         public NetworkChangeNotifier::Observer {
+class HostResolverImpl : public HostResolver {
  public:
   // The index into |job_pools_| for the various job pools. Pools with a higher
   // index have lower priority.
@@ -88,6 +87,7 @@ class HostResolverImpl : public HostResolver,
   virtual void CancelRequest(RequestHandle req);
   virtual void AddObserver(HostResolver::Observer* observer);
   virtual void RemoveObserver(HostResolver::Observer* observer);
+  virtual void Flush();
 
   // Set address family, and disable IPv6 probe support.
   virtual void SetDefaultAddressFamily(AddressFamily address_family);
@@ -180,9 +180,6 @@ class HostResolverImpl : public HostResolver,
                        int request_id,
                        const RequestInfo& info);
 
-  // NetworkChangeNotifier::Observer methods:
-  virtual void OnIPAddressChanged();
-
   // Notify IPv6ProbeJob not to call back, and discard reference to the job.
   void DiscardIPv6ProbeJob();