marijnh/CodeMirror — pull request #2390 by Dignifiedquire (2014-03-19 11:20:13+00:00)
Title: [v4] Only call signalLater if cm exists.

If the document has no `cm` instance attached it results in an error calling `signalLater` without an emitter. This only calls `signalLater` when there is a `cm` instance.