Move ReadFileToString to the base namespace.

base/process/internal_linux.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 "base/process/internal_linux.h"
 
 #include <unistd.h>
 
 #include <map>
 #include <string>
@@ skipping 36 matching lines @@
     return 0;
   }
   return pid;
 }
 
 bool ReadProcFile(const FilePath& file, std::string* buffer) {
   buffer->clear();
   // Synchronously reading files in /proc is safe.
   ThreadRestrictions::ScopedAllowIO allow_io;
 
-  if (!file_util::ReadFileToString(file, buffer)) {
+  if (!ReadFileToString(file, buffer)) {
     DLOG(WARNING) << "Failed to read " << file.MaybeAsASCII();
     return false;
   }
   return !buffer->empty();
 }
 
 bool ReadProcStats(pid_t pid, std::string* buffer) {
   FilePath stat_file = internal::GetProcPidDir(pid).Append(kStatFile);
   return ReadProcFile(stat_file, buffer);
 }
@@ skipping 113 matching lines @@
   // which means the answer is 100.
   // It may be the case that this value is always 100.
   static const int kHertz = sysconf(_SC_CLK_TCK);
 
   return TimeDelta::FromMicroseconds(
       Time::kMicrosecondsPerSecond * clock_ticks / kHertz);
 }
 
 }  // namespace internal
 }  // namespace base