Errors while running "ionic build --prod"

**Ionic version:** (check one with "x")
(For Ionic 1.x issues, please use https://github.com/ionic-team/ionic-v1)
[ ] **2.x**
[ x ] **3.x**
[ ] **4.x**

**I'm submitting a ...** (check one with "x")
[ x ] bug report
[ ] feature request

**Current behavior:**

While running with command "ionic cordova build android --prod --release" I got an error like below:

Module not found: Error: Can't resolve '../../node_modules/hj/flow/ReturnTaskUserControl.ngfactory' in 'F:\HJAGP\src\Android\BuildAndroid\AndroidApp\src\app'

resolve '../../node_modules/hj/flow/ReturnTaskUserControl.ngfactory' in 'F:\HJAGP\src\Android\BuildAndroid\AndroidApp\src\app'

  using description file: F:\HJAGP\src\Android\BuildAndroid\AndroidApp\package.json (relative path: ./src/app)

    Field 'browser' doesn't contain a valid alias configuration

  after using description file: F:\HJAGP\src\Android\BuildAndroid\AndroidApp\package.json (relative path: ./src/app)

    using description file: F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\package.json (relative path: ./ReturnTaskUserControl.ngfactory)

      no extension

        Field 'browser' doesn't contain a valid alias configuration

        F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory doesn't exist

      .ts

        Field 'browser' doesn't contain a valid alias configuration

        F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory.ts doesn't exist

      .js

        Field 'browser' doesn't contain a valid alias configuration

        F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory.js doesn't exist

      .json

        Field 'browser' doesn't contain a valid alias configuration

        F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory.json doesn't exist

      as directory

        F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory doesn't exist

[F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory]

[F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory.ts]

[F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory.js]

[F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory.json]

[F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\hj\flow\ReturnTaskUserControl.ngfactory]

 @ ./src/app/app.module.ngfactory.js 38:0-82

 @ ./src/app/main.ts

    at BuildError.Error (native)

    at new BuildError (F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\@ionic\app-scripts\dist\util\errors.js:16:28)

    at callback (F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\@ionic\app-scripts\dist\webpack.js:121:28)

    at emitRecords.err (F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\webpack\lib\Compiler.js:269:13)

    at Compiler.emitRecords (F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\webpack\lib\Compiler.js:375:38)

    at emitAssets.err (F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\webpack\lib\Compiler.js:262:10)

    at applyPluginsAsyncSeries1.err (F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\webpack\lib\Compiler.js:368:12)

    at next (F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\tapable\lib\Tapable.js:218:11)

    at Compiler.compiler.plugin (F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\webpack\lib\performance\SizeLimitsPlugin.js:99:4)

    at Compiler.applyPluginsAsyncSeries1 (F:\HJAGP\src\Android\BuildAndroid\AndroidApp\node_modules\tapable\lib\Tapable.js:222:13)

**Expected behavior:**

**Steps to reproduce:**

I tried running ".\node_modules\\.bin\ngc" but got no errors (screenshot below):

**Other information:**

**Ionic info:** (run `ionic info` from a terminal/cmd prompt and paste output below):

cli packages: (C:\Users\Administrator\AppData\Roaming\npm\node_modules)


    @ionic/cli-utils  : 1.19.1

    ionic (Ionic CLI) : 3.19.1

global packages:

    cordova (Cordova CLI) : 8.0.0

    Gulp CLI              : CLI version 3.9.1 Local version 3.9.1

local packages:

    @ionic/app-scripts : 3.1.8

    Cordova Platforms  : none

    Ionic Framework    : ionic-angular 3.9.2

System:

    Android SDK Tools : 25.2.3

    Node              : v6.9.1

    npm               : 3.10.8

    OS                : Windows 7

Environment Variables:

    ANDROID_HOME : G:\Android\sdk

Misc:

    backend : legacy

Start by reproducing `ionic cordova build android --prod --release` and compare it with the reported successful `ngc` command. Trace the module resolution failure through `src/app/app.module.ngfactory.js`, `src/app/main.ts`, and the referenced `@ionic/app-scripts/dist/webpack.js`; done means the production build no longer fails on the missing `.ngfactory` module.

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