Split servoshell into Desktop and common part (#32457)

* servoshell: Move desktop files

Move files related to winit into a desktop module.
This is a preparation to merge the android and ohos apps into
servoshell.

* servoshell: Format imports

* servoshell: Move panic hook into separate file

* servoshell: Move desktop main

* Consider ohos as not desktop

* servoshell: Adjust dependencies for shared code

* servoshell: Remove native-bluetooth from default features

There currently is no good way to have target specific default features.

* Rename desktop_main.rs to cli.rs

* Remove todo

ports/servoshell/panic_hook.rs

@@ -0,0 +1,47 @@
+/* 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::io::Write;
+use std::panic::PanicInfo;
+use std::{env, thread};
+
+use log::{error, warn};
+use servo::config::opts;
+
+pub(crate) fn panic_hook(info: &PanicInfo) {
+    warn!("Panic hook called.");
+    let msg = match info.payload().downcast_ref::<&'static str>() {
+        Some(s) => *s,
+        None => match info.payload().downcast_ref::<String>() {
+            Some(s) => &**s,
+            None => "Box<Any>",
+        },
+    };
+    let current_thread = thread::current();
+    let name = current_thread.name().unwrap_or("<unnamed>");
+    let stderr = std::io::stderr();
+    let mut stderr = stderr.lock();
+    if let Some(location) = info.location() {
+        let _ = writeln!(
+            &mut stderr,
+            "{} (thread {}, at {}:{})",
+            msg,
+            name,
+            location.file(),
+            location.line()
+        );
+    } else {
+        let _ = writeln!(&mut stderr, "{} (thread {})", msg, name);
+    }
+    if env::var("RUST_BACKTRACE").is_ok() {
+        let _ = crate::backtrace::print(&mut stderr);
+    }
+    drop(stderr);
+
+    if opts::get().hard_fail && !opts::get().multiprocess {
+        std::process::exit(1);
+    }
+
+    error!("{}", msg);
+}