Merge pull request #1690 from pandamicro/develop-3.0

Refactor #4365: Fix bug
Fixed #4277: fixed a bug of UILoadingBar that its width is incorrect.
Merge pull request #1691 from dingpinglv/Iss4277_ReleaseV3.0

Fixed #4277: fixed a bug of UILoadingBar that its width is incorrect.
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