feat(common): generate closure-locale.ts to tree shake locale data (#18907)

Closure will only keep the data for the locale defined in `goog.LOCALE`

PR Close #18907

tools/gulp-tasks/cldr.js

@@ -25,5 +25,16 @@ module.exports = {
       fs.mkdirSync(cldrDataFolder);
     }
     cldrDownloader(path.join(__dirname, 'cldr/cldr-urls.json'), cldrDataFolder, done);
-  }
+  },
+
+  closure: gulp => done => {
+    const {RELATIVE_I18N_DATA_FOLDER} = require('./cldr/extract');
+    console.log(RELATIVE_I18N_DATA_FOLDER, fs.existsSync(RELATIVE_I18N_DATA_FOLDER));
+    if (!fs.existsSync(RELATIVE_I18N_DATA_FOLDER)) {
+      throw new Error(
+          `You must run "gulp cldr:extract" before you can create the closure-locale.ts file`);
+    }
+    const localeAll = require('./cldr/closure');
+    return localeAll(gulp, done);
+  },
 };