修复空内容时,点击打印,关闭打印,出现了null的localstorage值
添加utils用例
Merge pull request #178 from worry127722/dev-1.4.0

Dev 1.4.0
[test]
Merge branch 'dev-1.4.0' of https://github.com/fex-team/ueditor into dev-1.4.0
Merge pull request #28 from fex-team/dev-1.4.0

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