Bug 1700241 - Mark click event as position-less event when accesskey of label element is pressed; r=masayuki

The click event dispatched for accesskey on other elements is marked as position-less event.
And other simulated click events are also marked as position-less, e.g. click() call, keydown Enter ...

label element should just behave the same on accesskey for consistency.

It is not clear on spec, see https://github.com/w3c/csswg-drafts/issues/1070,
but blink/webkit both returns 0 for offset{X|Y}.

Differential Revision: https://phabricator.services.mozilla.com/D109451

dom/html/HTMLLabelElement.cpp

@@ -191,15 +191,9 @@ bool HTMLLabelElement::PerformAccesskey(bool aKeyCausesActivation,
     }
 
     // Click on it if the users prefs indicate to do so.
-    WidgetMouseEvent event(aIsTrustedEvent, eMouseClick, nullptr,
-                           WidgetMouseEvent::eReal);
-    event.mInputSource = MouseEvent_Binding::MOZ_SOURCE_KEYBOARD;
-
     AutoPopupStatePusher popupStatePusher(
         aIsTrustedEvent ? PopupBlocker::openAllowed : PopupBlocker::openAbused);
-
-    EventDispatcher::Dispatch(static_cast<nsIContent*>(this), presContext,
-                              &event);
+    DispatchSimulatedClick(this, aIsTrustedEvent, presContext);
   }
 
   return aKeyCausesActivation;

testing/web-platform/tests/uievents/interface/keyboard-accesskey-click-event.html

@@ -7,12 +7,14 @@
 <p>Tests that a keyboard access key to press a button will fire only the click event</p>
 <button id="button" accesskey="g">Click Me with Shift+Alt+g or on Mac with Control+Option+g</button>
 <input id="inputbutton" type="button" accesskey="b" value="Click me with Shift+Alt+b or on Mac with Control+Option+b">
+<label id="label" accesskey="l">Click Me with Shift+Alt+l or on Mac with Control+Option+l</label>
 
 <script>
 let button = document.getElementById("button");
 let inputbutton = document.getElementById("inputbutton");
 let radiobutton = document.getElementById("radiobutton");
-let elementList = [button, inputbutton];
+let label = document.getElementById("label");
+let elementList = [button, inputbutton, label];
 let eventLog = [];
 const eventList = ["pointerdown", "pointerup", "mousedown", "mouseup", "click"];
 elementList.forEach((el)=>{eventList.forEach((ev)=>el.addEventListener(ev, (e)=>{
@@ -24,12 +26,21 @@ elementList.forEach((el)=>{eventList.forEach((ev)=>el.addEventListener(ev, (e)=>
         assert_equals(e.pointerId, 0, "Click's pointerId has default value");
         assert_equals(e.pointerType, "", "Click's pointerType has default value");
       }
+      assert_equals(e.screenX, 0, "Click's screenX has default value");
+      assert_equals(e.screenY, 0, "Click's screenY has default value");
+      assert_equals(e.clientX, 0, "Click's clientX has default value");
+      assert_equals(e.clientY, 0, "Click's clientY has default value");
+      assert_equals(e.pageX, 0, "Click's pageX has default value");
+      assert_equals(e.pageY, 0, "Click's pageY has default value");
+      // https://github.com/w3c/csswg-drafts/issues/1070
+      assert_equals(e.offsetX, 0, "Click's offsetX should have default value");
+      assert_equals(e.offsetY, 0, "Click's offsetY should have default value");
     });
   }
 }));});
 let currentTest;
-let testElements = [button, inputbutton];
-let accesskeyMap = new Map([[button, "g"], [inputbutton, "b"]]);
+let testElements = [button, inputbutton, label];
+let accesskeyMap = new Map([[button, "g"], [inputbutton, "b"], [label, "l"]]);
 testElements.forEach((el)=>promise_test((test)=> new Promise(async (resolve,reject)=>{
   currentTest = test;
   eventLog = [];