Currently resource_bundle.cc & resource_bundle_android.cc use one single file for locating locale strings. We plan to refactor it so that they use a priority queue of files instead.

It would pave way for several tasks:
1. De-duplicate monochrome's chrome & webview locale paks. This task requires loading at least two locale paks.
2. Adding more languages & shrinking current locale paks by de-duplicate similar locale paks, e.g. en-US & en-CA etc. This task requires loading multiple locale paks.