Move WriteFile and WriteFileDescriptor from file_util to base namespace.

components/policy/core/common/cloud/resource_cache.cc

Index: components/policy/core/common/cloud/resource_cache.cc
diff --git a/components/policy/core/common/cloud/resource_cache.cc b/components/policy/core/common/cloud/resource_cache.cc
index a68e66d47b841bebcc6dcbfbc1edc6d90baaea32..76221d14ba18438f9b3f694721baaa8da2a93424 100644
--- a/components/policy/core/common/cloud/resource_cache.cc
+++ b/components/policy/core/common/cloud/resource_cache.cc
@@ -85,7 +85,7 @@ bool ResourceCache::Store(const std::string& key,
   int size = base::checked_cast<int>(data.size());
   return VerifyKeyPathAndGetSubkeyPath(key, true, subkey, &subkey_path) &&
          base::DeleteFile(subkey_path, false) &&
-         (file_util::WriteFile(subkey_path, data.data(), size) == size);
+         (base::WriteFile(subkey_path, data.data(), size) == size);
 }
 
 bool ResourceCache::Load(const std::string& key,