fixed #2269 add a condition to LabelTest for LabelTTFStrokeShadowTest
Merge branch 'master' of https://github.com/cocos2d/cocos2d-js-tests into Iss2269_FixBugForLabelTest
Merge pull request #175 from dingpinglv/Iss2269_FixBugForLabelTest

fixed #2269 add a condition to LabelTest for LabelTTFStrokeShadowTest