This PR changes the way we are reading values from `.env` to allow
absent keys to pass `undefined` forward, and being ignored when
generating gn args, as opposed to have our build commands providing a
default in the absence of the key. This change will allow defaults to be
stored in `.gn` files, rather than always being overwritten by our build
command.
Improper default overwritting is what caused the crash relating to these
two PRs:
https://github.com/brave/brave-core/pull/28463https://github.com/brave/brave-core/pull/29891
* Refactor url proxy helper method out for use by all platforms.
* Move geolocation build flag to shared location for all platforms.
* Use shared redirect helper on iOS.
* Move static redirect helper, geolocation build flag, safe browsing build flag to components.
cdesouza-chromium