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

2 files changed, 7 insertions, 11 deletions

diff --git a/net/tools/fetch/fetch_client.cc b/net/tools/fetch/fetch_client.cc
index d6ba673..9e2a21c 100644
--- a/net/tools/fetch/fetch_client.cc
+++ b/net/tools/fetch/fetch_client.cc
@@ -133,7 +133,7 @@ int main(int argc, char**argv) {
   MessageLoop loop(MessageLoop::TYPE_IO);
 
   scoped_refptr<net::HostResolver> host_resolver(
-      net::CreateSystemHostResolver(NULL));
+      net::CreateSystemHostResolver());
 
   scoped_refptr<net::ProxyService> proxy_service(
       net::ProxyService::CreateNull());
@@ -143,18 +143,14 @@ int main(int argc, char**argv) {
   scoped_ptr<net::HttpAuthHandlerFactory> http_auth_handler_factory(
       net::HttpAuthHandlerFactory::CreateDefault());
   if (use_cache) {
-    factory = new net::HttpCache(NULL, host_resolver, proxy_service,
-                                 ssl_config_service,
-                                 http_auth_handler_factory.get(),
-                                 NULL,
-                                 NULL,
-                                 net::HttpCache::DefaultBackend::InMemory(0));
+    factory = new net::HttpCache(host_resolver, proxy_service,
+        ssl_config_service, http_auth_handler_factory.get(), NULL, NULL,
+        net::HttpCache::DefaultBackend::InMemory(0));
   } else {
     factory = new net::HttpNetworkLayer(
-        net::ClientSocketFactory::GetDefaultFactory(), NULL, host_resolver,
+        net::ClientSocketFactory::GetDefaultFactory(), host_resolver,
         proxy_service, ssl_config_service, http_auth_handler_factory.get(),
-        NULL,
-        NULL);
+        NULL, NULL);
   }
 
   {
diff --git a/net/tools/hresolv/hresolv.cc b/net/tools/hresolv/hresolv.cc
index c3858ad..9c67070 100644
--- a/net/tools/hresolv/hresolv.cc
+++ b/net/tools/hresolv/hresolv.cc
@@ -447,7 +447,7 @@ int main(int argc, char** argv) {
       base::TimeDelta::FromSeconds(0));
 
   scoped_refptr<net::HostResolver> host_resolver(
-      new net::HostResolverImpl(NULL, cache, NULL, 100u));
+      new net::HostResolverImpl(NULL, cache, 100u));
   ResolverInvoker invoker(host_resolver.get());
   invoker.ResolveAll(hosts_and_times, options.async);