Auto merge of #10272 - creativcoder:implement-data-url-fetch, r=jdm

implements data-url fetching

Fixes #10165
jdm mentioned of decoupling the, payload loading mechanism to data_loader.rs. So accordingly a `decoder` method has been added to data_loader.

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tests/unit/net/fetch.rs

@@ -6,14 +6,15 @@ use hyper::header::{AccessControlAllowHeaders, AccessControlAllowOrigin};
 use hyper::header::{CacheControl, ContentLanguage, ContentType, Expires, LastModified};
 use hyper::header::{Headers, HttpDate, Location, SetCookie, Pragma};
 use hyper::method::Method;
+use hyper::mime::{Mime, TopLevel, SubLevel};
 use hyper::server::{Handler, Listening, Server};
 use hyper::server::{Request as HyperRequest, Response as HyperResponse};
 use hyper::status::StatusCode;
 use hyper::uri::RequestUri;
 use net::fetch::methods::{fetch, fetch_async};
+use net_traits::AsyncFetchListener;
 use net_traits::request::{Origin, RedirectMode, Referer, Request, RequestMode};
 use net_traits::response::{CacheState, Response, ResponseBody, ResponseType};
-use net_traits::{AsyncFetchListener};
 use std::rc::Rc;
 use std::sync::mpsc::{Sender, channel};
 use std::sync::{Arc, Mutex};
@@ -108,6 +109,33 @@ fn test_fetch_aboutblank() {
     assert!(*fetch_response.body.lock().unwrap() == ResponseBody::Done(vec![]));
 }
 
+#[test]
+fn test_fetch_data() {
+
+    let url = Url::parse("data:text/html,<p>Servo</p>").unwrap();
+    let origin = Origin::Origin(url.origin());
+    let request = Request::new(url, Some(origin), false);
+    request.same_origin_data.set(true);
+    let expected_resp_body = "<p>Servo</p>".to_owned();
+    let fetch_response = fetch(Rc::new(request));
+
+    assert!(!fetch_response.is_network_error());
+    assert_eq!(fetch_response.headers.len(), 1);
+    let content_type: &ContentType = fetch_response.headers.get().unwrap();
+    assert!(**content_type == Mime(TopLevel::Text, SubLevel::Html, vec![]));
+    let resp_body = fetch_response.body.lock().unwrap();
+
+    match *resp_body {
+        ResponseBody::Done(ref val) => {
+            assert_eq!(val, &expected_resp_body.into_bytes());
+        }
+        ResponseBody::Receiving(_) => {
+            panic!();
+        },
+        ResponseBody::Empty => panic!(),
+    }
+}
+
 #[test]
 fn test_fetch_response_is_basic_filtered() {