Implement utility-side proxy resolver Mojo service.

net/proxy/proxy_list.h

Index: net/proxy/proxy_list.h
diff --git a/net/proxy/proxy_list.h b/net/proxy/proxy_list.h
index d57743e2df5abd5dd0d57df2326dba7db94b5d95..2bdb12d7bb359f52e0345faf2900c2f2846f6ac9 100644
--- a/net/proxy/proxy_list.h
+++ b/net/proxy/proxy_list.h
@@ -63,6 +63,9 @@ class NET_EXPORT_PRIVATE ProxyList {
   // this if !IsEmpty().
   const ProxyServer& Get() const;
 
+  // Returns all proxy servers in the list.
+  const std::vector<ProxyServer>& GetAll() const;
+
   // Sets the list by parsing the pac result |pac_string|.
   // Some examples for |pac_string|:
   //   "DIRECT"