title: Cannot read property 'kind' of undefined
body: <p>run the my project </p>
  
  <pre><code>ng build --prod --base-href="./"
  </code></pre>
  
  <p>getting below error message</p>
  
  <pre><code>ERROR in ./node_modules/ng-multiselect-dropdown/fesm2015/ng-multiselect-dropdown.js
  Module build failed (from ./node_modules/@angular-devkit/build-optimizer/src/build-optimizer/webpack-loader.js):
  TypeError: Cannot read property 'kind' of undefined
      at isAngularDecoratorMetadataExpression (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/src/transforms/scrub-file.js:265:35)
      at checkNodeForDecorators (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/src/transforms/scrub-file.js:77:21)
      at visitNodes (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16514:30)
      at Object.forEachChild (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16740:24)
      at checkNodeForDecorators (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/src/transforms/scrub-file.js:68:31)
      at visitNode (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16505:24)
      at Object.forEachChild (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16635:21)
      at checkNodeForDecorators (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/src/transforms/scrub-file.js:68:31)
      at visitNode (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16505:24)
      at Object.forEachChild (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16703:24)
      at checkNodeForDecorators (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/src/transforms/scrub-file.js:68:31)
      at visitNode (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16505:24)
      at Object.forEachChild (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16692:24)
      at checkNodeForDecorators (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/src/transforms/scrub-file.js:68:31)
      at visitNode (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16505:24)
      at Object.forEachChild (/home/gayathri/Desktop/webapp8/node_modules/@angular-devkit/build-optimizer/node_modules/typescript/lib/typescript.js:16599:21)
  </code></pre>