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

chrome/browser/autocomplete/autocomplete_input_unittest.cc

 // Copyright (c) 2012 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 "chrome/browser/autocomplete/autocomplete_input.h"
 
 #include "base/basictypes.h"
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "googleurl/src/url_parse.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 TEST(AutocompleteInputTest, InputType) {
   struct test_data {
     const string16 input;
     const AutocompleteInput::Type type;
   } input_cases[] = {
@@ skipping 224 matching lines @@
     SCOPED_TRACE(input_cases[i].input);
     AutocompleteInput input(input_cases[i].input,
                             input_cases[i].cursor_position,
                             string16(), GURL(), true, false, true,
                             AutocompleteInput::ALL_MATCHES);
     EXPECT_EQ(input_cases[i].normalized_input, input.text());
     EXPECT_EQ(input_cases[i].normalized_cursor_position,
               input.cursor_position());
   }
 }