Auto merge of #10154 - stjepang:fix-local-urls-only-10147, r=KiChjang

Fix #10147: Correctly handle flag local_urls_only

In function Request::fetch_main, flag local_urls_only (if set)
should allow fetching local urls only. Before this change, the flag had
the inverse behaviour.

Fixes #10147.
Test with: `./mach test-unit -p net fetch::test_fetch_with_local_urls_only`

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components/net/fetch/methods.rs

@@ -112,9 +112,9 @@ fn main_fetch(request: Rc<Request>, cors_flag: bool, recursive_flag: bool) -> Re
     // Step 2
     if request.local_urls_only {
         match &*request.current_url().scheme {
-            "about" | "blob" | "data" | "filesystem" => response = Some(Response::network_error()),
+            "about" | "blob" | "data" | "filesystem" => (), // Ok, the URL is local.
-            _ => { }
+            _ => response = Some(Response::network_error())
-        };
+        }
     }
 
     // Step 3

components/net_traits/request.rs

@@ -152,7 +152,7 @@ impl Request {
     pub fn new(url: Url,
                origin: Option<Origin>,
                is_service_worker_global_scope: bool) -> Request {
-         Request {
+        Request {
             method: RefCell::new(Method::Get),
             local_urls_only: false,
             sandboxed_storage_area_urls: false,

tests/unit/net/fetch.rs

@@ -282,6 +282,38 @@ fn test_fetch_response_is_opaque_redirect_filtered() {
     }
 }
 
+#[test]
+fn test_fetch_with_local_urls_only() {
+    // If flag `local_urls_only` is set, fetching a non-local URL must result in network error.
+
+    static MESSAGE: &'static [u8] = b"";
+    let handler = move |_: HyperRequest, response: HyperResponse| {
+        response.send(MESSAGE).unwrap();
+    };
+    let (mut server, server_url) = make_server(handler);
+
+    let do_fetch = |url: Url| {
+        let origin = Origin::Origin(url.origin());
+        let mut request = Request::new(url, Some(origin), false);
+        request.referer = Referer::NoReferer;
+
+        // Set the flag.
+        request.local_urls_only = true;
+
+        let wrapped_request = Rc::new(request);
+        fetch(wrapped_request)
+    };
+
+    let local_url = Url::parse("about:blank").unwrap();
+    let local_response = do_fetch(local_url);
+    let server_response = do_fetch(server_url);
+
+    let _ = server.close();
+
+    assert!(!local_response.is_network_error());
+    assert!(server_response.is_network_error());
+}
+
 fn test_fetch_redirect_count(message: &'static [u8], redirect_cap: u32) -> Response {
 
     let handler = move |request: HyperRequest, mut response: HyperResponse| {