Auto merge of #9456 - g-k:global-resize-event, r=KiChjang

Add onresize handler to GlobalEventHandlers

Rebased: https://github.com/servo/servo/pull/8006

Fixes #7996

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components/script/dom/htmlelement.rs

@@ -162,6 +162,24 @@ impl HTMLElementMethods for HTMLElement {
         }
     }
 
+    // https://html.spec.whatwg.org/multipage/#handler-onresize
+    fn GetOnresize(&self) -> Option<Rc<EventHandlerNonNull>> {
+        if self.is_body_or_frameset() {
+            window_from_node(self).GetOnload()
+        } else {
+            self.upcast::<EventTarget>().get_event_handler_common("resize")
+        }
+    }
+
+    // https://html.spec.whatwg.org/multipage/#handler-onresize
+    fn SetOnresize(&self, listener: Option<Rc<EventHandlerNonNull>>) {
+        if self.is_body_or_frameset() {
+            window_from_node(self).SetOnresize(listener);
+        } else {
+            self.upcast::<EventTarget>().set_event_handler_common("resize", listener)
+        }
+    }
+
     // https://html.spec.whatwg.org/multipage/#dom-click
     fn Click(&self) {
         if let Some(i) = self.downcast::<HTMLInputElement>() {

components/script/dom/macros.rs

@@ -333,6 +333,7 @@ macro_rules! error_event_handler(
 macro_rules! global_event_handlers(
     () => (
         event_handler!(load, GetOnload, SetOnload);
+        event_handler!(resize, GetOnresize, SetOnresize);
         global_event_handlers!(NoOnload);
 
     );

components/script/dom/webidls/EventHandler.webidl

@@ -34,6 +34,7 @@ interface GlobalEventHandlers {
            attribute EventHandler onreset;
            attribute EventHandler onsubmit;
            attribute EventHandler ontoggle;
+           attribute EventHandler onresize;
 };
 
 [NoInterfaceObject]