servo: Merge #14270 - Disable the debugger on Android until mio works…

… on Android (from larsbergstrom:disable_android_debugger); r=nox

<!-- Please describe your changes on the following line: -->
r? nox

The recent change to `ws-rs` introduced a dependency on `mio`, which depends on `nix`, which does not build on Android (nix-rust/nix#313). I've disabled the debugger in this change.

Fixes #14171

cc mmatyas

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- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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Source-Repo: https://github.com/servo/servo
Source-Revision: 9c6f6ebf3e789c251f34d865a4a713988ba81cdb

UltraBlame original commit: 9d91cefb5476e1da0840406029ce219d3d99aef1

servo/components/debugger/Cargo.toml

@@ -13,4 +13,6 @@ crate_type = ["rlib"]
 [dependencies]
 log = "0.3.5"
 util = {path = "../util"}
+
+[target.'cfg(not(target_os = "android"))'.dependencies]
 ws = "0.5.3"

servo/components/debugger/lib.rs

@@ -5,11 +5,13 @@
 #[macro_use]
 extern crate log;
 extern crate util;
+#[cfg(not(target_os = "android"))]
 extern crate ws;
 
 use std::sync::mpsc;
 use std::sync::mpsc::channel;
 use util::thread::spawn_named;
+#[cfg(not(target_os = "android"))]
 use ws::{Builder, CloseCode, Handler, Handshake};
 
 enum Message {
@@ -18,10 +20,12 @@ enum Message {
 
 pub struct Sender(mpsc::Sender<Message>);
 
+#[cfg(not(target_os = "android"))]
 struct Connection {
     sender: ws::Sender
 }
 
+#[cfg(not(target_os = "android"))]
 impl Handler for Connection {
     fn on_open(&mut self, _: Handshake) -> ws::Result<()> {
         debug!("Connection opened.");
@@ -37,6 +41,7 @@ impl Handler for Connection {
     }
 }
 
+#[cfg(not(target_os = "android"))]
 pub fn start_server(port: u16) -> Sender {
     debug!("Starting server.");
     let (sender, receiver) = channel();
@@ -60,10 +65,21 @@ pub fn start_server(port: u16) -> Sender {
     Sender(sender)
 }
 
+#[cfg(target_os = "android")]
+pub fn start_server(_: u16) -> Sender {
+    panic!("Debugger is not supported on Android");
+}
+
+#[cfg(not(target_os = "android"))]
 pub fn shutdown_server(sender: &Sender) {
     debug!("Shutting down server.");
     let &Sender(ref sender) = sender;
     if let Err(_) = sender.send(Message::ShutdownServer) {
         warn!("Failed to shut down server.");
     }
 }
+
+#[cfg(target_os = "android")]
+pub fn shutdown_server(_: &Sender) {
+    panic!("Debugger is not supported on Android");
+}