Prior to this commit, default value for LOCALE_ID was not setup for Closure Compiler. In Closure Compiler, we can use `goog.LOCALE` as a default value, which will be replaced at build time with current locale.
PR Close#31519
This is needed as:
- closure declares globals itself for minified names, which sometimes clobber our `ng` global
- we can't declare a closure extern as the namespace `ng` is already used within Google for typings for angularJS (via `goog.provide('ng....')`).
