3 files changed, 17 insertions, 13 deletions
diff --git a/components/script/dom/bindings/global.rs b/components/script/dom/bindings/global.rs
index 051a28439bd..e62573b5a9a 100644
--- a/components/script/dom/bindings/global.rs
+++ b/components/script/dom/bindings/global.rs
@@ -18,7 +18,6 @@ use js::{JSCLASS_IS_DOMJSCLASS, JSCLASS_IS_GLOBAL};
 use js::glue::{IsWrapper, UnwrapObject};
 use js::jsapi::{CurrentGlobalOrNull, GetGlobalForObjectCrossCompartment};
 use js::jsapi::{JSContext, JSObject, JS_GetClass};
-use task_source::file_reading::FileReadingTaskSource;
 
 /// A freely-copyable reference to a rooted global object.
 #[derive(Copy, Clone)]
@@ -54,15 +53,6 @@ impl<'a> GlobalRef<'a> {
             GlobalRef::Worker(ref worker) => worker.get_cx(),
         }
     }
-
-    /// `ScriptChan` used to send messages to the event loop of this global's
-    /// thread.
-    pub fn file_reading_task_source(&self) -> FileReadingTaskSource {
-        match *self {
-            GlobalRef::Window(ref window) => window.file_reading_task_source(),
-            GlobalRef::Worker(ref worker) => worker.file_reading_task_source(),
-        }
-    }
 }
 
 impl<'a> Reflectable for GlobalRef<'a> {
diff --git a/components/script/dom/filereader.rs b/components/script/dom/filereader.rs
index ebfb5060a58..2872aa2d325 100644
--- a/components/script/dom/filereader.rs
+++ b/components/script/dom/filereader.rs
@@ -333,8 +333,9 @@ impl FileReader {
             return Err(Error::InvalidState);
         }
         // Step 2
+        let global = self.global_scope();
         if blob.IsClosed() {
-            let exception = DOMException::new(&self.global_scope(), DOMErrorName::InvalidStateError);
+            let exception = DOMException::new(&global, DOMErrorName::InvalidStateError);
             self.error.set(Some(&exception));
 
             self.dispatch_progress_event(atom!("error"), 0, None);
@@ -354,8 +355,8 @@ impl FileReader {
         let fr = Trusted::new(self);
         let gen_id = self.generation_id.get();
 
-        let wrapper = self.global_scope().get_runnable_wrapper();
-        let task_source = self.global().r().file_reading_task_source();
+        let wrapper = global.get_runnable_wrapper();
+        let task_source = global.file_reading_task_source();
 
         spawn_named("file reader async operation".to_owned(), move || {
             perform_annotated_read_operation(gen_id, load_data, blob_contents, fr, task_source, wrapper)
diff --git a/components/script/dom/globalscope.rs b/components/script/dom/globalscope.rs
index fd5046c64c6..553393e3195 100644
--- a/components/script/dom/globalscope.rs
+++ b/components/script/dom/globalscope.rs
@@ -36,6 +36,7 @@ use std::collections::HashMap;
 use std::collections::hash_map::Entry;
 use std::ffi::CString;
 use std::panic;
+use task_source::file_reading::FileReadingTaskSource;
 use time::{Timespec, get_time};
 use timers::{IsInterval, OneshotTimerCallback, OneshotTimerHandle};
 use timers::{OneshotTimers, TimerCallback};
@@ -457,6 +458,18 @@ impl GlobalScope {
         }
         unreachable!();
     }
+
+    /// Channel to send messages to the file reading task source of
+    /// this of this global scope.
+    pub fn file_reading_task_source(&self) -> FileReadingTaskSource {
+        if let Some(window) = self.downcast::<Window>() {
+            return window.file_reading_task_source();
+        }
+        if let Some(worker) = self.downcast::<WorkerGlobalScope>() {
+            return worker.file_reading_task_source();
+        }
+        unreachable!();
+    }
 }
 
 fn timestamp_in_ms(time: Timespec) -> u64 {