Implement file reading task source

And remove superfluous FileReaderEvent enum

components/script/task_source/file_reading.rs

@@ -2,19 +2,72 @@
  * 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 script_runtime::{CommonScriptMsg, ScriptChan};
-use script_thread::MainThreadScriptMsg;
-use std::sync::mpsc::Sender;
+use dom::domexception::DOMErrorName;
+use dom::filereader::{FileReader, TrustedFileReader, GenerationId, ReadMetaData};
+use script_runtime::{CommonScriptMsg, ScriptThreadEventCategory, ScriptChan};
+use script_thread::{Runnable, RunnableWrapper};
+use std::sync::Arc;
+use task_source::TaskSource;
 
 #[derive(JSTraceable)]
-pub struct FileReadingTaskSource(pub Sender<MainThreadScriptMsg>);
+pub struct FileReadingTaskSource(pub Box<ScriptChan + Send + 'static>);
 
-impl ScriptChan for FileReadingTaskSource {
-    fn send(&self, msg: CommonScriptMsg) -> Result<(), ()> {
-        self.0.send(MainThreadScriptMsg::Common(msg)).map_err(|_| ())
-    }
-
-    fn clone(&self) -> Box<ScriptChan + Send> {
-        box FileReadingTaskSource((&self.0).clone())
+impl Clone for FileReadingTaskSource {
+    fn clone(&self) -> FileReadingTaskSource {
+        FileReadingTaskSource(self.0.clone())
+    }
+}
+
+impl TaskSource for FileReadingTaskSource {
+    fn queue_with_wrapper<T>(&self,
+                             msg: Box<T>,
+                             wrapper: &RunnableWrapper)
+                             -> Result<(), ()>
+                             where T: Runnable + Send + 'static {
+        self.0.send(CommonScriptMsg::RunnableMsg(ScriptThreadEventCategory::FileRead,
+                                                 wrapper.wrap_runnable(msg)))
+    }
+}
+
+pub struct FileReadingRunnable {
+    task: FileReadingTask,
+}
+
+impl FileReadingRunnable {
+    pub fn new(task: FileReadingTask) -> Box<FileReadingRunnable> {
+        box FileReadingRunnable {
+            task: task
+        }
+    }
+}
+
+impl Runnable for FileReadingRunnable {
+    fn handler(self: Box<FileReadingRunnable>) {
+        self.task.handle_task();
+    }
+}
+
+#[allow(dead_code)]
+pub enum FileReadingTask {
+    ProcessRead(TrustedFileReader, GenerationId),
+    ProcessReadData(TrustedFileReader, GenerationId),
+    ProcessReadError(TrustedFileReader, GenerationId, DOMErrorName),
+    ProcessReadEOF(TrustedFileReader, GenerationId, ReadMetaData, Arc<Vec<u8>>),
+}
+
+impl FileReadingTask {
+    pub fn handle_task(self) {
+        use self::FileReadingTask::*;
+
+        match self {
+            ProcessRead(reader, gen_id) =>
+                FileReader::process_read(reader, gen_id),
+            ProcessReadData(reader, gen_id) =>
+                FileReader::process_read_data(reader, gen_id),
+            ProcessReadError(reader, gen_id, error) =>
+                FileReader::process_read_error(reader, gen_id, error),
+            ProcessReadEOF(reader, gen_id, metadata, blob_contents) =>
+                FileReader::process_read_eof(reader, gen_id, metadata, blob_contents),
+        }
     }
 }