DevTools: track more elements panel user actions

third_party/WebKit/Source/devtools/front_end/elements/ElementsTreeOutline.js

Index: third_party/WebKit/Source/devtools/front_end/elements/ElementsTreeOutline.js
diff --git a/third_party/WebKit/Source/devtools/front_end/elements/ElementsTreeOutline.js b/third_party/WebKit/Source/devtools/front_end/elements/ElementsTreeOutline.js
index 4ee0efa5336c873969ef9ea02bb9379dcb110afe..1c2742e096af50514d35f07cf206065c6ae6da9d 100644
--- a/third_party/WebKit/Source/devtools/front_end/elements/ElementsTreeOutline.js
+++ b/third_party/WebKit/Source/devtools/front_end/elements/ElementsTreeOutline.js
@@ -73,6 +73,7 @@ Elements.ElementsTreeOutline = class extends UI.TreeOutline {
     this._selectedDOMNode = null;
 
     this._visible = false;
+    this._firstTimeSelectedNodeChanged = true;

[pfeldman, 2017/02/08 19:04:48]

nit: typically you go from false to true. "this._reportedNodeSelectedUMA"

[chenwilliam, 2017/02/10 22:53:38]

Done.

 
     this._popoverHelper = new UI.PopoverHelper(this._element);
     this._popoverHelper.initializeCallbacks(this._getPopoverAnchor.bind(this), this._showPopover.bind(this));
@@ -393,6 +394,9 @@ Elements.ElementsTreeOutline = class extends UI.TreeOutline {
    * @param {boolean} focus
    */
   _selectedNodeChanged(focus) {
+    if (!this._firstTimeSelectedNodeChanged)

[chenwilliam, 2017/02/08 01:10:21]

It's hacky, but I don't want to include first-time use since many of those are
just people opening DevTools and don't reflect actual intent to inspect another
node.

It's in a similar vein to "this._notFirstInspectElement" in ElementsPanel.js

+      Host.userMetrics.actionTaken(Host.UserMetrics.Action.ElementsTreeOutlineSelectNode);
+    this._firstTimeSelectedNodeChanged = false;
     this.dispatchEventToListeners(
         Elements.ElementsTreeOutline.Events.SelectedNodeChanged, {node: this._selectedDOMNode, focus: focus});
   }