Net: fold websocket and http tokio runtime into one (#31771)

* net: use the same tokio runtime in websocket loader

#31648

* readability

* license

components/net/async_runtime.rs

@@ -0,0 +1,12 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use std::sync::Mutex;
+
+use lazy_static::lazy_static;
+use tokio::runtime::Runtime;
+
+lazy_static! {
+    pub static ref HANDLE: Mutex<Option<Runtime>> = Mutex::new(Some(Runtime::new().unwrap()));
+}