Adds support for the DHCP portion of the WPAD (proxy auto-discovery) protocol.

net/proxy/proxy_service.cc

Index: net/proxy/proxy_service.cc
diff --git a/net/proxy/proxy_service.cc b/net/proxy/proxy_service.cc
index ca3629ebcdcdb6361921b2daf14d0b1bd7acd984..98e0e834922ffd3848e1fc9e05702100a737c2f6 100644
--- a/net/proxy/proxy_service.cc
+++ b/net/proxy/proxy_service.cc
@@ -393,7 +393,7 @@ ProxyService::ProxyService(ProxyConfigService* config_service,
 ProxyService* ProxyService::CreateUsingV8ProxyResolver(
     ProxyConfigService* proxy_config_service,
     size_t num_pac_threads,
-    ProxyScriptFetcher* proxy_script_fetcher,
+    URLProxyScriptFetcher* proxy_script_fetcher,
     HostResolver* host_resolver,
     NetLog* net_log) {
   DCHECK(proxy_config_service);
@@ -739,7 +739,7 @@ int ProxyService::DidFinishResolvingProxy(ProxyInfo* result,
 }
 
 void ProxyService::SetProxyScriptFetcher(
-    ProxyScriptFetcher* proxy_script_fetcher) {
+    URLProxyScriptFetcher* proxy_script_fetcher) {
   DCHECK(CalledOnValidThread());
   State previous_state = ResetProxyConfig(false);
   proxy_script_fetcher_.reset(proxy_script_fetcher);
@@ -747,7 +747,7 @@ void ProxyService::SetProxyScriptFetcher(
     ApplyProxyConfigIfAvailable();
 }
 
-ProxyScriptFetcher* ProxyService::GetProxyScriptFetcher() const {
+URLProxyScriptFetcher* ProxyService::GetProxyScriptFetcher() const {
   DCHECK(CalledOnValidThread());
   return proxy_script_fetcher_.get();
 }