无法读取未定义的属性“hasOwnProperty”

Question

我已将我们的项目升级到 Angular 7，一切正常。但是，当我执行 ngserve --aot 或使用 aot = true 构建产品版本时，出现以下运行时错误：

error: Uncaught (in promise): TypeError: Cannot read property 'hasOwnProperty' of undefined
TypeError: Cannot read property 'hasOwnProperty' of undefined
at constructTimingAst (http://localhost:4200/vendor.js:2316:15)
at AnimationAstBuilderVisitor.push../node_modules/@angular/animations/fesm5/browser.js.AnimationAstBuilderVisitor.visitAnimate (http://localhost:4200/vendor.js:2025:25)
at visitDslNode (http://localhost:4200/vendor.js:1759:28)
at http://localhost:4200/vendor.js:2003:61
at Array.map (<anonymous>)
at AnimationAstBuilderVisitor.push../node_modules/@angular/animations/fesm5/browser.js.AnimationAstBuilderVisitor.visitSequence (http://localhost:4200/vendor.js:2003:35)
at visitDslNode (http://localhost:4200/vendor.js:1755:28)
at AnimationAstBuilderVisitor.push../node_modules/@angular/animations/fesm5/browser.js.AnimationAstBuilderVisitor.visitQuery (http://localhost:4200/vendor.js:2235:25)
at visitDslNode (http://localhost:4200/vendor.js:1771:28)
at http://localhost:4200/vendor.js:2003:61

有什么想法吗。