bluetooth: Move writeValue to mojo

content/child/mojo/type_converters.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.
 
 #include <stddef.h>
 #include <utility>
 
 #include "mojo/public/cpp/bindings/array.h"
+#include "third_party/WebKit/public/platform/WebString.h"
 #include "third_party/WebKit/public/platform/WebVector.h"
 
 namespace mojo {
 
 template <typename T, typename U>
 struct TypeConverter<Array<T>, blink::WebVector<U>> {
   static Array<T> Convert(const blink::WebVector<U>& vector) {
     Array<T> array(vector.size());
     for (size_t i = 0; i < vector.size(); ++i)
       array[i] = TypeConverter<T, U>::Convert(vector[i]);
     return std::move(array);
   }
 };
 
+template <>
+struct TypeConverter<String, blink::WebString> {

[please use gerrit instead, 2016/03/16 22:09:30]

This should not be necessary now that
https://codereview.chromium.org/1751563002/ landed. You should add "'for_blink':
true" variable to the mojo target instead. That will make mojo use WTF::String
directly. This avoids string copies.

[ortuno, 2016/03/17 17:15:52]

That's for WTF types. This is a WebString so I still need to use the type
converter. Once we get rid of the content/renderer layer we will be able to use
WTF types directly.

+  static String Convert(const blink::WebString& web_string) {
+    return String(web_string.utf8());
+  }
+};
+
 }  // namespace mojo