Implement a ProfilerActor struct.

This is sufficient to make the profiler tab show up in Firefox's devtools.

components/devtools/actors/profiler.rs

@@ -0,0 +1,34 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+use actor::{Actor, ActorRegistry};
+
+use rustc_serialize::json;
+use std::net::TcpStream;
+
+pub struct ProfilerActor {
+    name: String,
+}
+
+impl Actor for ProfilerActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    fn handle_message(&self,
+                      _registry: &ActorRegistry,
+                      _msg_type: &str,
+                      _msg: &json::Object,
+                      _stream: &mut TcpStream) -> Result<bool, ()> {
+        Ok(false)
+    }
+}
+
+impl ProfilerActor {
+    pub fn new(name: String) -> ProfilerActor {
+        ProfilerActor {
+            name: name,
+        }
+    }
+}