Merge pull request #6856 from Dhilan007/v3_labelfix

close issue#5277:Label:It could be possible that for using outline and invoking 'Director::setContentScaleFactor' cause label show nothing.
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issue #5277:Label:It could be possible that for using outline and invoking 'Director::setContentScaleFactor' cause label show nothing.
Merge pull request #6857 from Dhilan007/v3_labelfix

issue #5277:Label:It could be possible that for using outline and invoking 'Director::setContentScaleFactor' cause label show nothing.