Mojo C++ bindings: support mapping mojo string to WTF::String.

mojo/public/cpp/bindings/tests/struct_traits_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 "base/bind.h"
 #include "base/callback.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
 #include "mojo/public/cpp/bindings/interface_request.h"
 #include "mojo/public/cpp/bindings/tests/rect_blink.h"
 #include "mojo/public/cpp/bindings/tests/rect_chromium.h"
 #include "mojo/public/cpp/bindings/tests/struct_with_traits_impl.h"
+#include "mojo/public/cpp/bindings/tests/variant_test_util.h"
 #include "mojo/public/interfaces/bindings/tests/struct_with_traits.mojom.h"
 #include "mojo/public/interfaces/bindings/tests/test_native_types.mojom-blink.h"
 #include "mojo/public/interfaces/bindings/tests/test_native_types.mojom-chromium.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace mojo {
 namespace test {
 namespace {
 
-// Converts a request of Interface1 to a request of Interface0. Interface0 and
-// Interface1 are expected to be two variants of the same mojom interface.
-// In real-world use cases, users shouldn't need to worry about this. Because it
-// is rare to deal with two variants of the same interface in the same app.
-template <typename Interface0, typename Interface1>
-InterfaceRequest<Interface0> ConvertInterfaceRequest(
-    InterfaceRequest<Interface1> request) {
-  DCHECK_EQ(0, strcmp(Interface0::Name_, Interface1::Name_));
-  InterfaceRequest<Interface0> result;
-  result.Bind(request.PassMessagePipe());
-  return result;
-}
-
 template <typename T>
 void DoExpectResult(const T& expected,
                     const base::Closure& callback,
                     const T& actual) {
   EXPECT_EQ(expected.x(), actual.x());
   EXPECT_EQ(expected.y(), actual.y());
   EXPECT_EQ(expected.width(), actual.width());
   EXPECT_EQ(expected.height(), actual.height());
   callback.Run();
 }
@@ skipping 189 matching lines @@
         EXPECT_EQ(input.get_uint32(), passed.get_uint32());
         EXPECT_EQ(input.get_uint64(), passed.get_uint64());
         EXPECT_EQ(input.get_string(), passed.get_string());
         loop.Quit();
       });
   loop.Run();
 }
 
 }  // namespace test
 }  // namespace mojo