* [libraries] Remove UseSystemResourceKeys true default

* [libraries] Remove UseSystemResourceKeys for iOS

* [libraries] Resolve WebSockets System resource keys activeissue

* [tests] Move default feature switches from libraries to functional tests

* [tests] Move Browser wasm default switches into FuntionalTests scope

* Add Browser OS condition

* Move DefaultFeatureSwitches initialization to FunctionalTests project

* Consolidate trimming framework library features and condition for libraries with EnableAggressiveTrimming

* [testing][EAT] Revert trimming framework library features to browser defaults for enable aggressive trimming

* [tests] Add Xamarin Android, Xamarin Mac/iOS, and Wasm feature defaults to Functional tests

* Fixup tabs to spaces

* Add common feature switches, links, and cleanup

* Cleanup Xamarin Android link
Co-authored-by: NMitchell Hwang <mitchell.hwang@microsoft.com>