fix(@angular-devkit/build-angular): ensure i18n extraction sourcemaps are fully configured

Some Webpack loaders use loader context flags to control sourcemap generation. This fix ensures that Webpack will set the appropriate flags for loaders to leverage.

(cherry picked from commit fe90b76)

Author: clydin

packages/angular_devkit/build_angular/src/extract-i18n/index.ts

@@ -21,7 +21,7 @@ import { ExecutionTransformer } from '../transforms';
 import { createI18nOptions } from '../utils/i18n-options';
 import { assertCompatibleAngularVersion } from '../utils/version';
 import { generateBrowserWebpackConfigFromContext } from '../utils/webpack-browser-config';
-import { getAotConfig, getCommonConfig, getStatsConfig } from '../webpack/configs';
+import { getAotConfig, getBrowserConfig, getCommonConfig, getStatsConfig } from '../webpack/configs';
 import { createWebpackLoggingCallback } from '../webpack/utils/stats';
 import { Format, Schema } from './schema';
 
@@ -184,6 +184,8 @@ export async function execute(
       scripts: [],
       styles: [],
       deleteOutputPath: false,
+      extractLicenses: false,
+      subresourceIntegrity: false,
     },
     context,
     (wco) => {
@@ -211,6 +213,7 @@ export async function execute(
       const partials = [
         { plugins: [new NoEmitPlugin()] },
         getCommonConfig(wco),
+        getBrowserConfig(wco),
         // Only use VE extraction if not using Ivy
         getAotConfig(wco, !usingIvy),
         getStatsConfig(wco),