Auto merge of #10725 - frewsxcv:net-cleanup, r=KiChjang

A few minor `net` component cleanups.

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components/net/cookie.rs

@@ -66,7 +66,7 @@ impl Cookie {
 
         // Step 7
         let mut path = cookie.path.unwrap_or("".to_owned());
-        if path.is_empty() || path.as_bytes()[0] != b'/' {
+        if path.chars().next() != Some('/') {
             let url_path = request.serialize_path();
             let url_path = url_path.as_ref().map(|path| &**path);
             path = Cookie::default_path(url_path.unwrap_or("")).to_owned();
@@ -96,7 +96,7 @@ impl Cookie {
     // http://tools.ietf.org/html/rfc6265#section-5.1.4
     pub fn default_path(request_path: &str) -> &str {
         // Step 2
-        if request_path.is_empty() || !request_path.starts_with("/") {
+        if request_path.chars().next() != Some('/') {
             return "/";
         }
 

components/net/file_loader.rs

@@ -44,17 +44,14 @@ fn read_block(reader: &mut File) -> Result<ReadStatus, String> {
 
 fn read_all(reader: &mut File, progress_chan: &ProgressSender, cancel_listener: &CancellationListener)
             -> Result<LoadResult, String> {
-    loop {
-        if cancel_listener.is_cancelled() {
-            let _ = progress_chan.send(Done(Err("load cancelled".to_owned())));
-            return Ok(LoadResult::Cancelled);
-        }
-
+    while !cancel_listener.is_cancelled() {
         match try!(read_block(reader)) {
             ReadStatus::Partial(buf) => progress_chan.send(Payload(buf)).unwrap(),
             ReadStatus::EOF => return Ok(LoadResult::Finished),
         }
     }
+    let _ = progress_chan.send(Done(Err("load cancelled".to_owned())));
+    Ok(LoadResult::Cancelled)
 }
 
 fn get_progress_chan(load_data: LoadData, file_path: PathBuf,

components/net/resource_thread.rs

@@ -227,17 +227,15 @@ impl CancellationListener {
     }
 
     pub fn is_cancelled(&self) -> bool {
-        match self.cancel_resource {
-            Some(ref resource) => {
-                match resource.cancel_receiver.try_recv() {
-                    Ok(_) => {
+        let resource = match self.cancel_resource {
+            Some(ref resource) => resource,
+            None => return false,  // channel doesn't exist!
+        };
+        if resource.cancel_receiver.try_recv().is_ok() {
             self.cancel_status.set(true);
             true
-                    },
-                    Err(_) => self.cancel_status.get(),
-                }
-            },
-            None => false,      // channel doesn't exist!
+        } else {
+            self.cancel_status.get()
         }
     }
 }