title: "React.createContext is not a function" - but I am not using it
body: <p>I am getting "React.createContext is not a function" error while running a react-native application. I searched for 'createContent' in the code, it doesn't exist.</p>
  
  <p>Any idea what may be the reason for the error.</p>
  
  <p>It is an iOS build of an app that is already running on android.</p>
  
  <p>Here is my package.json file:</p>
  
  <pre><code>{
    "name": "newapp",
    "version": "0.0.2",
    "private": true,
    "scripts": {
      "start": "node node_modules/react-native/local-cli/cli.js start",
      "test": "jest --verbose --coverage",
      "test:update": "jest --verbose --coverage --updateSnapshot",
      "test:watch": "jest --verbose --watch",
      "coverage": "jest --verbose --coverage &amp;&amp; xdg-open ./coverage/lcov-report/index.html",
      "lint": "npx eslint --fix ./src/*"
    },
    "dependencies": {
      "apollo-boost": "0.1.17",
      "axios": "^0.18.0",
      "babel": "^6.23.0",
      "buffer": "5.1.0",
      "cross-fetch": "^3.0.0",
      "enzyme": "^3.3.0",
      "graphql": "0.13.2",
      "graphql-tag": "2.10.0",
      "jasmine-react-helpers": "^0.2.2",
      "lodash": "4.17.5",
      "moment": "2.21.0",
      "query-string": "^6.1.0",
      "react": "16.2.0",
      "react-addons-test-utils": "^15.6.2",
      "react-apollo": "2.2.4",
      "react-dom": "^16.4.0",
      "react-native": "0.51.0",
      "react-native-elements": "0.19.0",
      "react-native-fabric": "^0.5.1",
      "react-native-htmlview": "^0.12.1",
      "react-native-link-preview": "^1.3.5",
      "react-native-login": "^0.0.1-alpha.2",
      "react-native-login-keycloak": "^1.0.2",
      "react-native-onesignal": "3.2.6",
      "react-native-push-notification": "https://github.com/Dhanraj-bidchat/react-native-push-notification.git",
      "react-native-sleek-loading-indicator": "^0.1.3",
      "react-native-spinkit": "^1.1.1",
      "react-native-svg": "6.2.2",
      "react-native-swipe-cards": "^0.1.1",
      "react-native-swiper": "1.5.13",
      "react-native-vector-icons": "4.5.0",
      "react-navigation": "1.5.6",
      "react-redux": "5.0.7",
      "redux": "^3.7.2",
      "redux-logger": "^3.0.6",
      "redux-persist": "5.9.1",
      "redux-thunk": "^2.2.0",
      "victory-native": "0.17.2",
      "whatwg-fetch": "2.0.4"
    },
    "devDependencies": {
      "babel-eslint": "^8.2.3",
      "babel-jest": "^22.4.4",
      "babel-plugin-dynamic-import-node": "^1.2.0",
      "babel-plugin-syntax-dynamic-import": "^6.18.0",
      "babel-plugin-transform-class-properties": "^6.24.1",
      "babel-plugin-transform-es2015-modules-commonjs": "^6.26.2",
      "babel-preset-env": "^1.7.0",
      "babel-preset-react-native": "4.0.0",
      "enzyme-adapter-react-16": "^1.1.1",
      "enzyme-to-json": "^3.3.4",
      "eslint": "^4.19.1",
      "eslint-config-standard": "^11.0.0",
      "eslint-plugin-import": "^2.12.0",
      "eslint-plugin-jest": "^21.17.0",
      "eslint-plugin-node": "^6.0.1",
      "eslint-plugin-only-warn": "^1.0.1",
      "eslint-plugin-promise": "^3.8.0",
      "eslint-plugin-react": "^7.9.1",
      "eslint-plugin-standard": "^3.1.0",
      "jest": "^23.5.0",
      "jest-resolve": "^23.0.0",
      "jest-serializer-enzyme": "^1.0.0",
      "react-native-mock-render": "^0.0.26",
      "react-test-renderer": "^16.3.2",
      "redux-mock-store": "^1.5.1",
      "sinon": "^5.0.10"
    },
    "jest": {
      "preset": "react-native",
      "setupFiles": [
        "./jest-setup.js"
      ],
      "snapshotSerializers": [
        "enzyme-to-json/serializer"
      ],
      "modulePaths": [
        "&lt;rootDir&gt;/src",
        "&lt;rootDir&gt;/node_modules"
      ],
      "transform": {
        "^.+\\.js$": "babel-jest",
        "^.+\\.jsx?$": "babel-jest"
      },
      "transformIgnorePatterns": [
        "node_modules/(?!(react-native-safe-area-view|react-navigation|react-native-htmlview|react-native-fabric|react-native-login|react-native-elements|react-native-vector-icons|react-native-spinkit|victory-pie|victory-chart|victory-core|react-native-svg|react-native|redux-persist|victory-native|react-native-swipe-cards|react-native-swiper)/)"
      ],
      "moduleNameMapper": {
        "\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$": "&lt;rootDir&gt;/assetsTransformer.js",
        "\\.(css|less)$": "&lt;rootDir&gt;/assetsTransformer.js"
      }
    }
  }
  </code></pre>