Bring base files from spree_core

app/models/spree/log_entry.rb

@@ -0,0 +1,16 @@
+module Spree
+  class LogEntry < ActiveRecord::Base
+    belongs_to :source, polymorphic: true
+
+    # Fix for #1767
+    # If a payment fails, we want to make sure we keep the record of it failing
+    after_rollback :save_anyway
+
+    def save_anyway
+      log = Spree::LogEntry.new
+      log.source  = source
+      log.details = details
+      log.save!
+    end
+  end
+end