Bug 1539265 - Add isMarkerPseudoElement function to layout/utils.js. r=jdescottes

Differential Revision: https://phabricator.services.mozilla.com/D25105

--HG--
extra : moz-landing-system : lando

devtools/server/actors/inspector/node.js

@@ -18,6 +18,7 @@ loader.lazyRequireGetter(this, "isAfterPseudoElement", "devtools/shared/layout/u
 loader.lazyRequireGetter(this, "isAnonymous", "devtools/shared/layout/utils", true);
 loader.lazyRequireGetter(this, "isBeforePseudoElement", "devtools/shared/layout/utils", true);
 loader.lazyRequireGetter(this, "isDirectShadowHostChild", "devtools/shared/layout/utils", true);
+loader.lazyRequireGetter(this, "isMarkerPseudoElement", "devtools/shared/layout/utils", true);
 loader.lazyRequireGetter(this, "isNativeAnonymous", "devtools/shared/layout/utils", true);
 loader.lazyRequireGetter(this, "isShadowAnonymous", "devtools/shared/layout/utils", true);
 loader.lazyRequireGetter(this, "isShadowHost", "devtools/shared/layout/utils", true);
@@ -127,6 +128,7 @@ const NodeActor = protocol.ActorClassWithSpec(nodeSpec, {
 
       attrs: this.writeAttrs(),
       customElementLocation: this.getCustomElementLocation(),
+      isMarkerPseudoElement: isMarkerPseudoElement(this.rawNode),
       isBeforePseudoElement: isBeforePseudoElement(this.rawNode),
       isAfterPseudoElement: isAfterPseudoElement(this.rawNode),
       isAnonymous: isAnonymous(this.rawNode),

devtools/shared/fronts/node.js

@@ -267,6 +267,9 @@ class NodeFront extends FrontClassWithSpec(nodeSpec) {
     return this._form.hasEventListeners;
   }
 
+  get isMarkerPseudoElement() {
+    return this._form.isMarkerPseudoElement;
+  }
   get isBeforePseudoElement() {
     return this._form.isBeforePseudoElement;
   }

devtools/shared/layout/utils.js

@@ -649,6 +649,17 @@ function isDirectShadowHostChild(node) {
 }
 exports.isDirectShadowHostChild = isDirectShadowHostChild;
 
+/**
+ * Determine whether a node is a ::marker pseudo.
+ *
+ * @param {DOMNode} node
+ * @return {Boolean}
+ */
+function isMarkerPseudoElement(node) {
+  return node.nodeName === "_moz_generated_content_marker";
+}
+exports.isMarkerPseudoElement = isMarkerPseudoElement;
+
 /**
  * Determine whether a node is a ::before pseudo.
  *