Use std::string instead of mojo::String in //net.

net/proxy/proxy_service_mojo_unittest.cc

 // 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.
 
 #include "net/proxy/proxy_service_mojo.h"
 
 #include <algorithm>
 #include <memory>
 #include <string>
 #include <utility>
@@ skipping 121 matching lines @@
 
     fetcher_ = new MockProxyScriptFetcher;
     proxy_service_ = CreateProxyServiceUsingMojoFactory(
         this, base::MakeUnique<ProxyConfigServiceFixed>(
                   ProxyConfig::CreateFromCustomPacURL(GURL(kPacUrl))),
         fetcher_, base::MakeUnique<DoNothingDhcpProxyScriptFetcher>(),
         &mock_host_resolver_, &net_log_, &network_delegate_);
   }
 
   std::unique_ptr<base::ScopedClosureRunner> CreateResolver(
-      const mojo::String& pac_script,
+      const std::string& pac_script,
       mojo::InterfaceRequest<interfaces::ProxyResolver> req,
       interfaces::ProxyResolverFactoryRequestClientPtr client) override {
     InProcessMojoProxyResolverFactory::GetInstance()->CreateResolver(
         pac_script, std::move(req), std::move(client));
     return base::MakeUnique<base::ScopedClosureRunner>(
         on_delete_closure_.closure());
   }
 
   TestNetworkDelegate network_delegate_;
   LoggingMockHostResolver mock_host_resolver_;
@@ skipping 105 matching lines @@
   EXPECT_THAT(callback.WaitForResult(), IsOk());
   EXPECT_EQ("DIRECT", info.ToPacString());
   EXPECT_EQ(0u, mock_host_resolver_.num_resolve());
 
   TestNetLogEntry::List entries;
   net_log_.GetEntries(&entries);
   CheckCapturedNetLogEntries(entries);
 }
 
 }  // namespace net