Mojo C++ bindings: add a new mode to generator to use native STL/WTF types

mojo/public/cpp/bindings/tests/e2e_perftest.cc

Index: mojo/public/cpp/bindings/tests/e2e_perftest.cc
diff --git a/mojo/public/cpp/bindings/tests/e2e_perftest.cc b/mojo/public/cpp/bindings/tests/e2e_perftest.cc
index df7f25a10c6cf7db5bfa9f0be541d4972f7f5f2e..66ac6dc76db6bc4155a25a247549d70b573f4500 100644
--- a/mojo/public/cpp/bindings/tests/e2e_perftest.cc
+++ b/mojo/public/cpp/bindings/tests/e2e_perftest.cc
@@ -28,7 +28,7 @@ class EchoServiceImpl : public test::EchoService {
   ~EchoServiceImpl() override;
 
   // |EchoService| methods:
-  void Echo(const mojo::String& test_data,
+  void Echo(const std::string& test_data,
             const EchoCallback& callback) override;
 
  private:
@@ -44,7 +44,7 @@ EchoServiceImpl::~EchoServiceImpl() {
   quit_closure_.Run();
 }
 
-void EchoServiceImpl::Echo(const mojo::String& test_data,
+void EchoServiceImpl::Echo(const std::string& test_data,
                            const EchoCallback& callback) {
   callback.Run(test_data);
 }
@@ -57,10 +57,10 @@ class PingPongTest {
 
  private:
   void DoPing();
-  void OnPingDone(mojo::String reply);
+  void OnPingDone(const std::string& reply);
 
   test::EchoServicePtr service_;
-  const base::Callback<void(mojo::String)> ping_done_callback_;
+  const base::Callback<void(const std::string&)> ping_done_callback_;
 
   int iterations_;
   int batch_size_;
@@ -106,7 +106,7 @@ void PingPongTest::DoPing() {
   }
 }
 
-void PingPongTest::OnPingDone(mojo::String reply) {
+void PingPongTest::OnPingDone(const std::string& reply) {
   DCHECK_GT(calls_outstanding_, 0);
   calls_outstanding_--;