shill: Update to build against libchrome-271506.

BUG=chromium:375032
TEST=`USE='cellular gdmwimax wimax vpn' FEATURES=test emerge-$BOARD platform2`

Change-Id: Ib7c8b2b290caa261cbb61d30cf8a361a1e3345e1
Reviewed-on: https://chromium-review.googlesource.com/201211
Tested-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>
Reviewed-by: Paul Stewart <pstew@chromium.org>
diff --git a/profile.cc b/profile.cc
index 475ac31..ab9b97b 100644
--- a/profile.cc
+++ b/profile.cc
@@ -322,7 +322,7 @@
                                        id.user_hash.c_str()));
   }
   string content = JoinString(lines, "");
-  size_t ret = file_util::WriteFile(path, content.c_str(), content.length());
+  size_t ret = base::WriteFile(path, content.c_str(), content.length());
   return ret == content.length();
 }