Mojo C++ bindings: switch WebKit mojom targets to use STL/WTF types.

content/browser/hyphenation/hyphenation_impl.cc

Index: content/browser/hyphenation/hyphenation_impl.cc
diff --git a/content/browser/hyphenation/hyphenation_impl.cc b/content/browser/hyphenation/hyphenation_impl.cc
index 5e6c3cda728f8b5f5b9da758e2edb8ea1be91808..32c9730e3e81aac378bcc80904d2e7be3e1c4762 100644
--- a/content/browser/hyphenation/hyphenation_impl.cc
+++ b/content/browser/hyphenation/hyphenation_impl.cc
@@ -65,7 +65,7 @@ void HyphenationImpl::Create(blink::mojom::HyphenationRequest request) {
                           std::move(request));
 }
 
-void HyphenationImpl::OpenDictionary(const mojo::String& locale,
+void HyphenationImpl::OpenDictionary(const std::string& locale,
                                      const OpenDictionaryCallback& callback) {
   mojo::ScopedHandle handle;
   if (IsValidLocale(locale)) {