Fast-fail WPAD detection.

net/proxy/proxy_script_decider.h

Index: net/proxy/proxy_script_decider.h
diff --git a/net/proxy/proxy_script_decider.h b/net/proxy/proxy_script_decider.h
index 9a77938ec8e4aef834281184e16d1d55913b9b3c..a5d8d7fdb77656a56964fa7e97645d37ff5fee9e 100644
--- a/net/proxy/proxy_script_decider.h
+++ b/net/proxy/proxy_script_decider.h
@@ -12,9 +12,12 @@
 #include "base/strings/string16.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
+#include "net/base/address_list.h"
 #include "net/base/completion_callback.h"
 #include "net/base/net_export.h"
 #include "net/base/net_log.h"
+#include "net/dns/host_resolver.h"
+#include "net/dns/single_request_host_resolver.h"
 #include "net/proxy/proxy_config.h"
 #include "net/proxy/proxy_resolver.h"
 #include "url/gurl.h"
@@ -103,12 +106,15 @@ class NET_EXPORT_PRIVATE ProxyScriptDecider {
 
   enum State {
     STATE_NONE,
+    STATE_QUICK_CHECK,
+    STATE_QUICK_CHECK_COMPLETE,
     STATE_WAIT,
     STATE_WAIT_COMPLETE,
     STATE_FETCH_PAC_SCRIPT,
     STATE_FETCH_PAC_SCRIPT_COMPLETE,
     STATE_VERIFY_PAC_SCRIPT,
     STATE_VERIFY_PAC_SCRIPT_COMPLETE,
+    STATE_FAILED,
   };
 
   // Returns ordered list of PAC urls to try for |config|.
@@ -118,6 +124,10 @@ class NET_EXPORT_PRIVATE ProxyScriptDecider {
   int DoLoop(int result);
   void DoCallback(int result);
 
+  int DoQuickCheck();
+  int DoQuickCheckComplete();
+  void OnQuickCheckComplete(base::Time started, int result);
+
   int DoWait();
   int DoWaitComplete(int result);
 
@@ -175,6 +185,10 @@ class NET_EXPORT_PRIVATE ProxyScriptDecider {
   ProxyConfig effective_config_;
   scoped_refptr<ProxyResolverScriptData> script_data_;
 
+  scoped_ptr<HostResolver> underlying_host_resolver_;
+  SingleRequestHostResolver host_resolver_;
+  AddressList wpad_addrs_;
+  base::OneShotTimer<ProxyScriptDecider> quick_check_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(ProxyScriptDecider);
 };