Merge branch '5300/ccr/elasticsearch_index' into 'master'

Modified find project method to return nil if project not found

See merge request gitlab-org/gitlab-ce!21168

app/views/search/results/_blob.html.haml

 - project = find_project_for_result_blob(blob)
+- return unless project
+
 - file_name, blob = parse_search_result(blob)
 - blob_link = project_blob_path(project, tree_join(blob.ref, file_name))