Auto merge of #8622 - frewsxcv:url-plugin, r=SimonSapin

Implement 'url!(..)' macro

https://github.com/servo/rust-url/issues/136

https://github.com/servo/rust-url/pull/137

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components/script/dom/document.rs

@@ -1388,7 +1388,7 @@ impl Document {
                      source: DocumentSource,
                      doc_loader: DocumentLoader)
                      -> Document {
-        let url = url.unwrap_or_else(|| Url::parse("about:blank").unwrap());
+        let url = url.unwrap_or_else(|| url!("about:blank"));
 
         let (ready_state, domcontentloaded_dispatched) = if source == DocumentSource::FromParser {
             (DocumentReadyState::Loading, false)

components/script/dom/htmliframeelement.rs

@@ -124,7 +124,7 @@ impl HTMLIFrameElement {
     pub fn process_the_iframe_attributes(&self) {
         let url = match self.get_url() {
             Some(url) => url.clone(),
-            None => Url::parse("about:blank").unwrap(),
+            None => url!("about:blank"),
         };
 
         self.navigate_child_browsing_context(url);

components/script/script_task.rs

@@ -1969,7 +1969,7 @@ impl ScriptTask {
         };
 
         if load_data.url.scheme == "javascript" {
-            load_data.url = Url::parse("about:blank").unwrap();
+            load_data.url = url!("about:blank");
         }
 
         resource_task.send(ControlMsg::Load(NetLoadData {