Remove mojo::String.

services/tracing/public/cpp/provider.cc

Index: services/tracing/public/cpp/provider.cc
diff --git a/services/tracing/public/cpp/provider.cc b/services/tracing/public/cpp/provider.cc
index 9b09b096d18c7fde2c286a762b102e700182d0a6..852f5d63f5266ebacc2bf90afb801f23df4c7876 100644
--- a/services/tracing/public/cpp/provider.cc
+++ b/services/tracing/public/cpp/provider.cc
@@ -150,7 +150,7 @@ void Provider::SendChunk(
   // The string will be empty if an error eccured or there were no trace
   // events. Empty string is not a valid chunk to record so skip in this case.
   if (!events_str->data().empty()) {
-    recorder_->Record(mojo::String(events_str->data()));
+    recorder_->Record(events_str->data());
   }
   if (!has_more_events) {
     recorder_.reset();