crash in MASViewContraint line 130

[weixianlove]

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Issue Info

Info	Value
Platform	e.g. ios/osx/tvos
Platform Version	e.g. 8.0
Masonry Version	e.g. 1.0
Integration Method	e.g. carthage/cocoapods/manually

Issue Description

我们SDK使用的1.0版本，我参照最新版本Masonry分类在SDK中增加了一个VIew的分类以支持safeArea,在SDK中正常运行，当SDK加入其它项目，且该项目也有Masonry（1.0）时，safeArae的调用会崩溃在该项目的 MASViewContraint 的 setSecondViewAttribute: 方法中，进入了NAAssert.
lldb信息如下：
(lldb) po [secondViewAttribute isKindOfClass:MASViewAttribute.class]
nil
(lldb) po [secondViewAttribute class]
MASViewAttribute

(lldb) po MASViewAttribute.class
MASViewAttribute

手动注释NSAssert 且拷贝上方代码:
_secondViewAttribute = secondViewAttribute;
UI正常如预期显示。。。。求解啊。。。