Add RetainedRef uses where needed.

content/browser/tracing/tracing_controller_impl_data_sinks.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 <utility>
 
 #include "base/bind.h"
 #include "base/files/file_util.h"
 #include "base/json/json_writer.h"
 #include "base/macros.h"
 #include "base/strings/pattern.h"
@@ skipping 16 matching lines @@
   explicit StringTraceDataEndpoint(CompletionCallback callback)
       : completion_callback_(callback) {}
 
   void ReceiveTraceFinalContents(
       scoped_ptr<const base::DictionaryValue> metadata,
       const std::string& contents) override {
     std::string tmp = contents;
     scoped_refptr<base::RefCountedString> str =
         base::RefCountedString::TakeString(&tmp);
 
-    BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
-                            base::Bind(completion_callback_,
-                                       base::Passed(std::move(metadata)), str));
+    BrowserThread::PostTask(
+        BrowserThread::UI, FROM_HERE,
+        base::Bind(completion_callback_, base::Passed(std::move(metadata)),
+                   base::RetainedRef(str)));
   }
 
  private:
   ~StringTraceDataEndpoint() override {}
 
   CompletionCallback completion_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(StringTraceDataEndpoint);
 };
 
@@ skipping 316 matching lines @@
   return new StringTraceDataEndpoint(callback);
 }
 
 scoped_refptr<TracingController::TraceDataEndpoint>
 TracingController::CreateFileEndpoint(const base::FilePath& file_path,
                                       const base::Closure& callback) {
   return new FileTraceDataEndpoint(file_path, callback);
 }
 
 }  // namespace content