Change ProxyRules to handle ProxyLists rather than just single ProxyServer instances.

net/proxy/proxy_list.cc

Index: net/proxy/proxy_list.cc
diff --git a/net/proxy/proxy_list.cc b/net/proxy/proxy_list.cc
index 1b2ecc73aef6269001dfff64e647d45499ecc5c8..4a4950119fcbdcc505231ea899c9d01b1f25fd7a 100644
--- a/net/proxy/proxy_list.cc
+++ b/net/proxy/proxy_list.cc
@@ -35,6 +35,10 @@ void ProxyList::Set(const std::string& proxy_uri_list) {
 
 void ProxyList::SetSingleProxyServer(const ProxyServer& proxy_server) {
   proxies_.clear();
+  AddProxyServer(proxy_server);
+}
+
+void ProxyList::AddProxyServer(const ProxyServer& proxy_server) {
   if (proxy_server.is_valid())
     proxies_.push_back(proxy_server);
 }
@@ -110,6 +114,13 @@ size_t ProxyList::size() const {
   return proxies_.size();
 }
 
+// Returns true if |*this| lists the same proxies as |other|.
+bool ProxyList::Equals(const ProxyList& other) const {
+  if (size() != other.size())
+    return false;
+  return proxies_ == other.proxies_;
+}
+
 const ProxyServer& ProxyList::Get() const {
   DCHECK(!proxies_.empty());
   return proxies_[0];