Move ReadFileToString to the base namespace.

chrome/browser/drive/fake_drive_service_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/drive/fake_drive_service.h"
 
 #include <string>
 #include <vector>
 
 #include "base/file_util.h"
@@ skipping 885 matching lines @@
       "file:2_file_resource_id",
       test_util::CreateCopyResultCallback(&error, &output_file_path),
       get_content_callback.callback(),
       base::Bind(&test_util::AppendProgressCallbackResult,
                  &download_progress_values));
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(HTTP_SUCCESS, error);
   EXPECT_EQ(output_file_path, kOutputFilePath);
   std::string content;
-  ASSERT_TRUE(file_util::ReadFileToString(output_file_path, &content));
+  ASSERT_TRUE(base::ReadFileToString(output_file_path, &content));
   // The content is "x"s of the file size specified in root_feed.json.
   EXPECT_EQ("This is some test content.", content);
   ASSERT_TRUE(!download_progress_values.empty());
   EXPECT_TRUE(base::STLIsSorted(download_progress_values));
   EXPECT_LE(0, download_progress_values.front().first);
   EXPECT_GE(26, download_progress_values.back().first);
   EXPECT_EQ(content, get_content_callback.GetConcatenatedData());
 }
 
 TEST_F(FakeDriveServiceTest, DownloadFile_NonexistingFile) {
@@ skipping 1366 matching lines @@
       test_util::CreateCopyResultCallback(&error, &resource_entry));
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(GDATA_NO_CONNECTION, error);
   EXPECT_FALSE(resource_entry);
 }
 
 }  // namespace
 
 }  // namespace drive