Bug 42018: Rebase to 115.2.1

Rebased our fork on top of upstream 115.2.1.

I've squashed everything since it was the first release anyway.

Closes tor-browser#42018 (closed).

/cc @richard

android-components/components/browser/engine-gecko/src/main/java/mozilla/components/browser/engine/gecko/fetch/GeckoViewFetchClient.kt

@@ -87,6 +87,7 @@ private fun Request.toWebRequest(): WebRequest = WebRequest.Builder(url)
     .addHeadersFrom(this)
     .addBodyFrom(this)
     .cacheMode(if (useCaches) CACHE_MODE_DEFAULT else CACHE_MODE_RELOAD)
+    .origin(origin)
     // Turn off bleeding-edge network features to avoid breaking core browser functionality.
     .beConservative(true)
     .build()