Move ReadFileToString to the base namespace.

tools/gn/command_gyp.cc

 // Copyright (c) 2013 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 <fstream>
 
 #include "base/atomicops.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
@@ skipping 51 matching lines @@
     subninjas->insert(filename);
 
     next_subninja = line_end;
   }
   return *first_subninja_offset != std::string::npos;
 }
 
 bool FixupBuildNinja(const BuildSettings* build_settings,
                      const base::FilePath& buildfile) {
   std::string contents;
-  if (!file_util::ReadFileToString(buildfile, &contents)) {
+  if (!base::ReadFileToString(buildfile, &contents)) {
     Err(Location(), "Could not load " + FilePathToUTF8(buildfile))
         .PrintToStdout();
     return false;
   }
 
   std::set<std::string> subninjas;
   size_t first_subninja_offset = 0;
   if (!SimpleNinjaParse(contents, &subninjas, &first_subninja_offset)) {
     Err(Location(), "Could not parse " + FilePathToUTF8(buildfile))
         .PrintToStdout();
@@ skipping 153 matching lines @@
         base::IntToString((end_gyp_time - begin_time).InMilliseconds()) +
         "ms)\n";
 
     OutputString(stats);
   }
 
   return 0;
 }
 
 }  // namespace commands