Massively simplify the NetworkChangeNotifier infrastructure:

  * Use a process-wide object (singleton pattern)
  * Create/destroy this object on the main thread, make it outlive all consumers
  * Make observer-related functions threadsafe

As a result, the notifier can now be used by any thread (eliminating things like NetworkChangeObserverProxy and NetworkChangeNotifierProxy, and expanding its usefulness); its creation and inner workings are much simplified (eliminating implementation-specific classes); and it is simpler to access (eliminating things like NetworkChangeNotifierThread and a LOT of passing pointers around).

BUG=none
TEST=Unittests; network changes still trigger notifications
Review URL: http://codereview.chromium.org/2802015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@50895 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 20 insertions, 25 deletions

diff --git a/net/spdy/spdy_http_stream_unittest.cc b/net/spdy/spdy_http_stream_unittest.cc
index c3b321a..d1d3546 100644
--- a/net/spdy/spdy_http_stream_unittest.cc
+++ b/net/spdy/spdy_http_stream_unittest.cc
@@ -55,7 +55,7 @@ class SessionDependencies {
         proxy_service(CreateNullProxyService()),
         ssl_config_service(new SSLConfigServiceDefaults),
         http_auth_handler_factory(HttpAuthHandlerFactory::CreateDefault()),
-        spdy_session_pool(new SpdySessionPool(NULL)) {}
+        spdy_session_pool(new SpdySessionPool()) {}
 
   // Custom proxy service dependency.
   explicit SessionDependencies(ProxyService* proxy_service)
@@ -63,7 +63,7 @@ class SessionDependencies {
         proxy_service(proxy_service),
         ssl_config_service(new SSLConfigServiceDefaults),
         http_auth_handler_factory(HttpAuthHandlerFactory::CreateDefault()),
-        spdy_session_pool(new SpdySessionPool(NULL)) {}
+        spdy_session_pool(new SpdySessionPool()) {}
 
   scoped_refptr<MockHostResolverBase> host_resolver;
   scoped_refptr<ProxyService> proxy_service;
@@ -74,8 +74,7 @@ class SessionDependencies {
 };
 
 HttpNetworkSession* CreateSession(SessionDependencies* session_deps) {
-  return new HttpNetworkSession(NULL,
-                                session_deps->host_resolver,
+  return new HttpNetworkSession(session_deps->host_resolver,
                                 session_deps->proxy_service,
                                 &session_deps->socket_factory,
                                 session_deps->ssl_config_service,
diff --git a/net/spdy/spdy_network_transaction_unittest.cc b/net/spdy/spdy_network_transaction_unittest.cc
index c6e1cb0..e912b78 100644
--- a/net/spdy/spdy_network_transaction_unittest.cc
+++ b/net/spdy/spdy_network_transaction_unittest.cc
@@ -55,7 +55,7 @@ class SessionDependencies {
         proxy_service(ProxyService::CreateNull()),
         ssl_config_service(new SSLConfigServiceDefaults),
         http_auth_handler_factory(HttpAuthHandlerFactory::CreateDefault()),
-        spdy_session_pool(new SpdySessionPool(NULL)) {
+        spdy_session_pool(new SpdySessionPool()) {
     // Note: The CancelledTransaction test does cleanup by running all tasks
     // in the message loop (RunAllPending).  Unfortunately, that doesn't clean
     // up tasks on the host resolver thread; and TCPConnectJob is currently
@@ -71,7 +71,7 @@ class SessionDependencies {
         proxy_service(proxy_service),
         ssl_config_service(new SSLConfigServiceDefaults),
         http_auth_handler_factory(HttpAuthHandlerFactory::CreateDefault()),
-        spdy_session_pool(new SpdySessionPool(NULL)) {}
+        spdy_session_pool(new SpdySessionPool()) {}
 
   scoped_refptr<MockHostResolverBase> host_resolver;
   scoped_refptr<ProxyService> proxy_service;
@@ -82,8 +82,7 @@ class SessionDependencies {
 };
 
 HttpNetworkSession* CreateSession(SessionDependencies* session_deps) {
-  return new HttpNetworkSession(NULL,
-                                session_deps->host_resolver,
+  return new HttpNetworkSession(session_deps->host_resolver,
                                 session_deps->proxy_service,
                                 &session_deps->socket_factory,
                                 session_deps->ssl_config_service,
diff --git a/net/spdy/spdy_session_pool.cc b/net/spdy/spdy_session_pool.cc
index c7e2e79..3374a2e 100644
--- a/net/spdy/spdy_session_pool.cc
+++ b/net/spdy/spdy_session_pool.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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.
 
@@ -14,17 +14,14 @@ static const size_t kMaxSessionsPerDomain = 1;
 
 int SpdySessionPool::g_max_sessions_per_domain = kMaxSessionsPerDomain;
 
-SpdySessionPool::SpdySessionPool(NetworkChangeNotifier* notifier)
-    : network_change_notifier_(notifier) {
-  if (network_change_notifier_)
-    network_change_notifier_->AddObserver(this);
+SpdySessionPool::SpdySessionPool() {
+  NetworkChangeNotifier::AddObserver(this);
 }
 
 SpdySessionPool::~SpdySessionPool() {
   CloseAllSessions();
 
-  if (network_change_notifier_)
-    network_change_notifier_->RemoveObserver(this);
+  NetworkChangeNotifier::RemoveObserver(this);
 }
 
 scoped_refptr<SpdySession> SpdySessionPool::Get(
@@ -85,6 +82,10 @@ void SpdySessionPool::Remove(const scoped_refptr<SpdySession>& session) {
     RemoveSessionList(session->host_port_pair());
 }
 
+void SpdySessionPool::OnIPAddressChanged() {
+  ClearSessions();
+}
+
 SpdySessionPool::SpdySessionList*
     SpdySessionPool::AddSessionList(const HostPortPair& host_port_pair) {
   DCHECK(sessions_.find(host_port_pair) == sessions_.end());
diff --git a/net/spdy/spdy_session_pool.h b/net/spdy/spdy_session_pool.h
index 08d01e0..3ea97f3 100644
--- a/net/spdy/spdy_session_pool.h
+++ b/net/spdy/spdy_session_pool.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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.
 
@@ -21,7 +21,6 @@ namespace net {
 class BoundNetLog;
 class ClientSocketHandle;
 class HttpNetworkSession;
-class NetworkChangeNotifier;
 class SpdySession;
 
 // This is a very simple pool for open SpdySessions.
@@ -30,7 +29,7 @@ class SpdySessionPool
     : public base::RefCounted<SpdySessionPool>,
       public NetworkChangeNotifier::Observer {
  public:
-  explicit SpdySessionPool(NetworkChangeNotifier* notifier);
+  SpdySessionPool();
 
   // Either returns an existing SpdySession or creates a new SpdySession for
   // use.
@@ -72,7 +71,7 @@ class SpdySessionPool
   // We flush all idle sessions and release references to the active ones so
   // they won't get re-used.  The active ones will either complete successfully
   // or error out due to the IP address change.
-  virtual void OnIPAddressChanged() { ClearSessions(); }
+  virtual void OnIPAddressChanged();
 
  private:
   friend class base::RefCounted<SpdySessionPool>;
@@ -100,8 +99,6 @@ class SpdySessionPool
   // This is our weak session pool - one session per domain.
   SpdySessionsMap sessions_;
 
-  NetworkChangeNotifier* const network_change_notifier_;
-
   static int g_max_sessions_per_domain;
 
   DISALLOW_COPY_AND_ASSIGN(SpdySessionPool);
diff --git a/net/spdy/spdy_session_unittest.cc b/net/spdy/spdy_session_unittest.cc
index 67dcb94..20b73d9 100644
--- a/net/spdy/spdy_session_unittest.cc
+++ b/net/spdy/spdy_session_unittest.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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.
 
@@ -41,7 +41,7 @@ class SessionDependencies {
       : host_resolver(new MockHostResolver),
         proxy_service(ProxyService::CreateNull()),
         ssl_config_service(new SSLConfigServiceDefaults),
-        spdy_session_pool(new SpdySessionPool(NULL)) {
+        spdy_session_pool(new SpdySessionPool()) {
   }
 
   scoped_refptr<MockHostResolverBase> host_resolver;
@@ -52,8 +52,7 @@ class SessionDependencies {
 };
 
 HttpNetworkSession* CreateSession(SessionDependencies* session_deps) {
-  return new HttpNetworkSession(NULL,
-                                session_deps->host_resolver,
+  return new HttpNetworkSession(session_deps->host_resolver,
                                 session_deps->proxy_service,
                                 &session_deps->socket_factory,
                                 session_deps->ssl_config_service,