build should not hash lazy styles

[xmlking]

Bug Report or Feature Request (mark with an x)

- [x] bug report -> please search issues before submitting
- [ ] feature request

Command (mark with an x)

- [ ] new
- [x] build
- [ ] serve
- [ ] test
- [ ] e2e
- [ ] generate
- [ ] add
- [ ] update
- [ ] lint
- [ ] xi18n
- [ ] run
- [ ] config
- [ ] help
- [ ] version
- [ ] doc

Versions

node  v10.7.0
npm 6.3.0

Angular CLI: 6.1.2
Node: 10.7.0
OS: darwin x64
Angular: 6.1.1
... animations, common, compiler, compiler-cli, core, forms
... http, language-service, platform-browser
... platform-browser-dynamic, router, service-worker

Package                            Version
------------------------------------------------------------
@angular-devkit/architect          0.7.2
@angular-devkit/build-angular      0.7.2
@angular-devkit/build-ng-packagr   0.7.2
@angular-devkit/build-optimizer    0.7.2
@angular-devkit/build-webpack      0.7.2
@angular-devkit/core               0.7.2
@angular-devkit/schematics         0.7.2
@angular/cdk                       6.4.2
@angular/cdk-experimental          6.4.2
@angular/cli                       6.1.2
@angular/flex-layout               6.0.0-beta.17
@angular/material                  6.4.2
@angular/material-moment-adapter   6.4.2
@angular/pwa                       0.7.2
@ngtools/json-schema               1.1.0
@ngtools/webpack                   6.1.2
@schematics/angular                0.7.2
@schematics/update                 0.7.2
ng-packagr                         4.0.1
rxjs                               6.2.2
typescript                         2.9.2
webpack                            4.9.2

Repro steps

git clone https://github.com/xmlking/ngx-starter-kit
# change  "outputHashing": "media" ->  "outputHashing": "all" in angular.json
ng build --project=webapp -c=production

The log given by the failure

chunk {20} assets/themes/purple-green.c17c75933c9deb385322.css (assets/themes/purple-green) 41.7 kB [initial] [rendered]
chunk {21} assets/themes/pink-bluegrey.78fd02deb5fb284bee86.css (assets/themes/pink-bluegrey) 41.7 kB [initial] [rendered]
chunk {22} assets/themes/indigo-pink.f4824af46022d121b324.css (assets/themes/indigo-pink) 41.7 kB [initial] [rendered]
chunk {23} assets/themes/deeppurple-amber.fc4d4a015e92cbb72237.css (assets/themes/deeppurple-amber) 41.6 kB [initial] [rendered]

Desired functionality

According to https://github.com/angular/angular-cli/blob/master/packages/angular_devkit/build_angular/test/browser/output-hashing_spec_large.ts#L167

Build command should not hash lazy styles , but it is hashing lazy files.

My Config: https://github.com/xmlking/ngx-starter-kit/blob/master/angular.json#L41

Mention any other details that might be useful

https://github.com/angular/angular-cli/blob/master/packages/angular_devkit/build_angular/test/browser/output-hashing_spec_large.ts#L167