Auto merge of #11225 - izgzhen:patch-input-element-file, r=Manishearth

Implement file related functionalities in htmlinputelement and related

- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy --faster` does not report any errors
- [x] These changes is related to #11131
- [x] These changes do not require tests because it is a partial implementation

1. Improve the `filemanager_thread` by adding type string and create `SelectedFile`
2. Fill several gaps in `htmlinputelement` implementation related to file type
3. Improve the `File` interface to accommodate the above changes
4. Integrate changes introduced by PR #11189

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components/net/filemanager_thread.rs

@@ -3,7 +3,9 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
-use net_traits::filemanager_thread::{FileManagerThreadMsg, FileManagerResult, FileManagerThreadError};
+use mime_guess::guess_mime_type_opt;
+use net_traits::filemanager_thread::{FileManagerThreadMsg, FileManagerResult};
+use net_traits::filemanager_thread::{SelectedFile, FileManagerThreadError};
 use std::cell::RefCell;
 use std::collections::HashMap;
 use std::fs::File;
@@ -17,15 +19,13 @@ pub struct FileManager {
     idmap: RefCell<HashMap<Uuid, PathBuf>>,
 }
 
-impl FileManager {
-    fn new(recv: IpcReceiver<FileManagerThreadMsg>) -> FileManager {
-        FileManager {
-            receiver: recv,
-            idmap: RefCell::new(HashMap::new()),
-        }
-    }
+pub trait FileManagerThreadFactory {
+    fn new() -> Self;
+}
 
-    pub fn new_thread() -> IpcSender<FileManagerThreadMsg> {
+impl FileManagerThreadFactory for IpcSender<FileManagerThreadMsg> {
+    /// Create a FileManagerThread
+    fn new() -> IpcSender<FileManagerThreadMsg> {
         let (chan, recv) = ipc::channel().unwrap();
 
         spawn_named("FileManager".to_owned(), move || {
@@ -34,6 +34,16 @@ impl FileManager {
 
         chan
     }
+}
+
+
+impl FileManager {
+    fn new(recv: IpcReceiver<FileManagerThreadMsg>) -> FileManager {
+        FileManager {
+            receiver: recv,
+            idmap: RefCell::new(HashMap::new()),
+        }
+    }
 
     /// Start the file manager event loop
     fn start(&mut self) {
@@ -49,7 +59,7 @@ impl FileManager {
 }
 
 impl FileManager {
-    fn select_file(&mut self, sender: IpcSender<FileManagerResult<(Uuid, PathBuf, u64)>>) {
+    fn select_file(&mut self, sender: IpcSender<FileManagerResult<SelectedFile>>) {
         // TODO: Pull the dialog UI in and get selected
         let selected_path = Path::new("");
 
@@ -63,7 +73,7 @@ impl FileManager {
         }
     }
 
-    fn select_files(&mut self, sender: IpcSender<FileManagerResult<Vec<(Uuid, PathBuf, u64)>>>) {
+    fn select_files(&mut self, sender: IpcSender<FileManagerResult<Vec<SelectedFile>>>) {
         let selected_paths = vec![Path::new("")];
 
         let mut replies = vec![];
@@ -81,7 +91,7 @@ impl FileManager {
         let _ = sender.send(Ok(replies));
     }
 
-    fn create_entry(&mut self, file_path: &Path) -> Option<(Uuid, PathBuf, u64)> {
+    fn create_entry(&mut self, file_path: &Path) -> Option<SelectedFile> {
         match File::open(file_path) {
             Ok(handler) => {
                 let id = Uuid::new_v4();
@@ -100,7 +110,19 @@ impl FileManager {
                 let filename = file_path.file_name();
 
                 match (epoch, filename) {
-                    (Ok(epoch), Some(filename)) => Some((id, Path::new(filename).to_path_buf(), epoch)),
+                    (Ok(epoch), Some(filename)) => {
+                        let filename_path = Path::new(filename);
+                        let mime = guess_mime_type_opt(filename_path);
+                        Some(SelectedFile {
+                            id: id,
+                            filename: filename_path.to_path_buf(),
+                            modified: epoch,
+                            type_string: match mime {
+                                Some(x) => format!("{}", x),
+                                None    => "".to_string(),
+                            },
+                        })
+                    }
                     _ => None
                 }
             },

components/net/resource_thread.rs

@@ -11,6 +11,7 @@ use cookie_storage::CookieStorage;
 use data_loader;
 use devtools_traits::{DevtoolsControlMsg};
 use file_loader;
+use filemanager_thread::FileManagerThreadFactory;
 use hsts::HstsList;
 use http_loader::{self, HttpState};
 use hyper::client::pool::Pool;
@@ -154,7 +155,8 @@ pub fn new_resource_threads(user_agent: String,
                             devtools_chan: Option<Sender<DevtoolsControlMsg>>,
                             profiler_chan: ProfilerChan) -> ResourceThreads {
     ResourceThreads::new(new_core_resource_thread(user_agent, devtools_chan, profiler_chan),
-                         StorageThreadFactory::new())
+                         StorageThreadFactory::new(),
+                         FileManagerThreadFactory::new())
 }