title: Repository is not clean
body: <p>Updating angular 7 to angular 8, I updated successfully upto <code>angular/cli angular/core</code> using the command <code>$ ng update @angular/cli@v8 @angular/core@v8</code>.
  And i used angular material also, so i want to update material then i update with <code>$ ng update @angular/material@v8</code>.
  But after running the command i got <code>Repository is not clean.  Please commit or stash any changes before updating.</code></p>
  
  <p>So I committed before changes to git, then again I tried with the same command, then also getting the same message. Now there are no files to commit or stash.</p>
  
  <p>This is the dependencies of the <code>package.json</code> files:
  <code>"dependencies": {
      "@angular/animations": "^8.0.0",
      "@angular/cdk": "^7.3.7",
      "@angular/common": "^8.0.0",
      "@angular/compiler": "^8.0.0",
      "@angular/core": "^8.0.0",
      "@angular/forms": "^8.0.0",
      "@angular/material": "^7.3.7",
      "@angular/platform-browser": "^8.0.0",
      "@angular/platform-browser-dynamic": "^8.0.0",
      "@angular/router": "^8.0.0",
      "core-js": "^2.5.4",
      "hammerjs": "^2.0.8",
      "ngx-loading": "^3.0.1",
      "rxjs": "6.5.2",
      "underscore": "^1.9.1",
      "zone.js": "~0.9.1"
    },
    "devDependencies": {
      "@angular-devkit/build-angular": "~0.800.0",
      "@angular/cli": "~8.0.2",
      "@angular/compiler-cli": "^8.0.0",
      "@angular/language-service": "^8.0.0",
      "@types/jasmine": "~2.8.6",
      "@types/jasminewd2": "~2.0.3",
      "@types/node": "~8.9.4",
      "bootstrap-sass": "^3.3.7",
      "codelyzer": "^5.0.1",
      "jasmine-core": "~2.99.1",
      "jasmine-spec-reporter": "~4.2.1",
      "karma": "~1.7.1",
      "karma-chrome-launcher": "~2.2.0",
      "karma-coverage-istanbul-reporter": "~2.0.0",
      "karma-jasmine": "~1.1.1",
      "karma-jasmine-html-reporter": "^0.2.2",
      "karma-scss-preprocessor": "^3.0.0",
      "protractor": "~5.3.0",
      "ts-node": "~5.0.1",
      "tslint": "~5.9.1",
      "typescript": "~3.4.5"
    }</code></p>
  
  <p>This is the message i got:
  <code>D:\test&gt;ng update @angular/material@v8
  Repository is not clean.  Please commit or stash any changes before updating.</code></p>
  
  <p>I delete the node_modules folder and reinstalled with the help of <code>$ npm install --save</code>. After installed i tried again, then also getting the same message. </p>
  
  <p>Does anyone know, how to update the material?</p>