Move ReadFileToString to the base namespace.

chrome/browser/policy/cloud/user_cloud_policy_store.cc

Index: chrome/browser/policy/cloud/user_cloud_policy_store.cc
diff --git a/chrome/browser/policy/cloud/user_cloud_policy_store.cc b/chrome/browser/policy/cloud/user_cloud_policy_store.cc
index 3fa53d5bfe95acdcd6739ced153b56db06391f63..3592b85933a64addc71915a535997f289bfc6dc6 100644
--- a/chrome/browser/policy/cloud/user_cloud_policy_store.cc
+++ b/chrome/browser/policy/cloud/user_cloud_policy_store.cc
@@ -56,7 +56,7 @@ policy::PolicyLoadResult LoadPolicyFromDisk(const base::FilePath& path) {
     return result;
   }
   std::string data;
-  if (!file_util::ReadFileToString(path, &data) ||
+  if (!base::ReadFileToString(path, &data) ||
       !result.policy.ParseFromArray(data.c_str(), data.size())) {
     LOG(WARNING) << "Failed to read or parse policy data from " << path.value();
     result.status = policy::LOAD_RESULT_LOAD_ERROR;