Mojo: Remove url type converters.

net/proxy/mojo_proxy_resolver_impl.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_PROXY_MOJO_PROXY_RESOLVER_IMPL_H_
 #define NET_PROXY_MOJO_PROXY_RESOLVER_IMPL_H_
 
 #include <map>
 #include <memory>
 #include <queue>
@@ skipping 12 matching lines @@
   explicit MojoProxyResolverImpl(
       std::unique_ptr<ProxyResolverV8Tracing> resolver);
 
   ~MojoProxyResolverImpl() override;
 
  private:
   class Job;
 
   // interfaces::ProxyResolver overrides.
   void GetProxyForUrl(
-      const mojo::String& url,
+      const GURL& url,
       interfaces::ProxyResolverRequestClientPtr client) override;
 
   void DeleteJob(Job* job);
 
   std::unique_ptr<ProxyResolverV8Tracing> resolver_;
   std::set<Job*> resolve_jobs_;
 
   DISALLOW_COPY_AND_ASSIGN(MojoProxyResolverImpl);
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_MOJO_PROXY_RESOLVER_IMPL_H_