Auto merge of #11368 - izgzhen:fix-filemanager-exit, r=asajeffrey

Fix FileManager thread panic and other misc improvements

- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy --faster` does not report any errors
- [x] There are tests for these changes

Changes:

- Add shut down logic for FileManager thread
- Add an unit test for filemanager_thread

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components/constellation/constellation.rs

@@ -38,6 +38,7 @@ use msg::constellation_msg::{SubpageId, WindowSizeData, WindowSizeType};
 use msg::constellation_msg::{self, PanicMsg};
 use msg::webdriver_msg;
 use net_traits::bluetooth_thread::BluetoothMethodMsg;
+use net_traits::filemanager_thread::FileManagerThreadMsg;
 use net_traits::image_cache_thread::ImageCacheThread;
 use net_traits::storage_thread::StorageThreadMsg;
 use net_traits::{self, ResourceThreads, IpcSend};
@@ -850,6 +851,11 @@ impl<LTF: LayoutThreadFactory, STF: ScriptThreadFactory> Constellation<LTF, STF>
         if let Err(e) = self.resource_threads.send(StorageThreadMsg::Exit) {
             warn!("Exit storage thread failed ({})", e);
         }
+
+        if let Err(e) = self.resource_threads.send(FileManagerThreadMsg::Exit) {
+            warn!("Exit storage thread failed ({})", e);
+        }
+
         if let Err(e) = self.bluetooth_thread.send(BluetoothMethodMsg::Exit) {
             warn!("Exit bluetooth thread failed ({})", e);
         }

components/net/filemanager_thread.rs

@@ -53,6 +53,7 @@ impl FileManager {
                 FileManagerThreadMsg::SelectFiles(sender) => self.select_files(sender),
                 FileManagerThreadMsg::ReadFile(sender, id) => self.read_file(sender, id),
                 FileManagerThreadMsg::DeleteFileID(id) => self.delete_fileid(id),
+                FileManagerThreadMsg::Exit => break,
             }
         }
     }

components/net_traits/filemanager_thread.rs

@@ -6,7 +6,7 @@ use ipc_channel::ipc::IpcSender;
 use std::path::PathBuf;
 use uuid::Uuid;
 
-#[derive(Deserialize, Serialize)]
+#[derive(Debug, Deserialize, Serialize)]
 pub struct SelectedFile {
     pub id: Uuid,
     pub filename: PathBuf,
@@ -28,6 +28,9 @@ pub enum FileManagerThreadMsg {
 
     /// Delete the FileID entry
     DeleteFileID(Uuid),
+
+    /// Shut down this thread
+    Exit,
 }
 
 pub type FileManagerResult<T> = Result<T, FileManagerThreadError>;

components/script/dom/file.rs

@@ -51,8 +51,6 @@ impl File {
     pub fn new_from_selected(window: &Window, selected: SelectedFile) -> Root<File> {
         let name = DOMString::from(selected.filename.to_str().expect("File name encoding error"));
 
-        // FIXME: fix this after PR #11221 is landed
-        let id = selected.id;
         let slice = DataSlice::empty();
 
         let global = GlobalRef::Window(window);