Auto merge of #6181 - brunoabinader:mouseover-status, r=larsbergstrom

Implement Msg::Status with serialized url upon mouseover

Credits for Mike Blumenkrantz (@zmike), I just rebased against trunk and
fixed the url serialization.

Fixes #6178.

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ports/cef/window.rs

@@ -316,6 +316,9 @@ impl WindowMethods for Window {
         browser.downcast().favicons.borrow_mut().push(url.to_string().clone());
     }
 
+    fn status(&self, _: Option<String>) {
+    }
+
     fn load_start(&self, back: bool, forward: bool) {
         let browser = self.cef_browser.borrow();
         let browser = match *browser {

ports/glutin/window.rs

@@ -554,6 +554,9 @@ impl WindowMethods for Window {
     fn set_page_url(&self, _: Url) {
     }
 
+    fn status(&self, _: Option<String>) {
+    }
+
     fn load_start(&self, _: bool, _: bool) {
     }
 
@@ -778,6 +781,9 @@ impl WindowMethods for Window {
     fn set_favicon(&self, _: Url) {
     }
 
+    fn status(&self, _: Option<String>) {
+    }
+
     fn prepare_for_composite(&self, _width: usize, _height: usize) -> bool {
         true
     }

ports/gonk/src/window.rs

@@ -803,6 +803,9 @@ impl WindowMethods for Window {
     fn set_page_url(&self, _: Url) {
     }
 
+    fn status(&self, _: Option<String>) {
+    }
+
     fn load_start(&self, _: bool, _: bool) {
     }