Use a direct include of strings headers in chrome/browser/d*/.

chrome/browser/diagnostics/diagnostics_model.h

 // Copyright (c) 2011 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.
 
 #ifndef CHROME_BROWSER_DIAGNOSTICS_DIAGNOSTICS_MODEL_H_
 #define CHROME_BROWSER_DIAGNOSTICS_DIAGNOSTICS_MODEL_H_
 
-#include "base/string16.h"
+#include "base/strings/string16.h"
 
 class CommandLine;
 
 // The chrome diagnostics system is a model-view-controller system. The Model
 // responsible for holding and running the individual tests and providing a
 // uniform interface for querying the outcome.
 // TODO(cpu): The view and the controller are not yet built.
 class DiagnosticsModel {
  public:
   // A particular test can be in one of the following states.
@@ skipping 49 matching lines @@
   // returned object.
   virtual TestInfo& GetTest(size_t id) = 0;
 };
 
 // The factory for the model. The main purpose is to hide the creation of
 // different models for different platforms.
 DiagnosticsModel* MakeDiagnosticsModel(const CommandLine& cmdline);
 
 
 #endif  // CHROME_BROWSER_DIAGNOSTICS_DIAGNOSTICS_MODEL_H_