DevTools: Remember the last focused widget.

third_party/WebKit/Source/devtools/front_end/ui/Widget.js

Index: third_party/WebKit/Source/devtools/front_end/ui/Widget.js
diff --git a/third_party/WebKit/Source/devtools/front_end/ui/Widget.js b/third_party/WebKit/Source/devtools/front_end/ui/Widget.js
index 8b6954c319136932f2d025684b4620f57949ca4d..81e02c3a6626948916d24f6c0ff22f6ec9ce79c9 100644
--- a/third_party/WebKit/Source/devtools/front_end/ui/Widget.js
+++ b/third_party/WebKit/Source/devtools/front_end/ui/Widget.js
@@ -48,6 +48,8 @@ WebInspector.Widget = function(isWebComponent)
     this._hideOnDetach = false;
     this._notificationDepth = 0;
     this._invalidationsSuspended = 0;
+    this._boundWasFocused = this.wasFocused.bind(this);
+    this._lastFocusedChild = null;
 }
 
 WebInspector.Widget.prototype = {
@@ -238,6 +240,9 @@ WebInspector.Widget.prototype = {
             this.detach();
         this._parentWidget = parentWidget;
         this._parentWidget._children.push(this);
+        if (!this._parentWidget._lastFocusedChild)
+            this._parentWidget._lastFocusedChild = this;
+        this._updateDefaultFocusedElementListener();
         this._isRoot = false;
     },
 
@@ -332,9 +337,12 @@ WebInspector.Widget.prototype = {
             var childIndex = this._parentWidget._children.indexOf(this);
             WebInspector.Widget.__assert(childIndex >= 0, "Attempt to remove non-child widget");
             this._parentWidget._children.splice(childIndex, 1);
+            if (this._parentWidget._lastFocusedChild === this)
+                this._parentWidget._lastFocusedChild = this._parentWidget._children[0] || null;
             this._parentWidget.childWasDetached(this);
             var parent = this._parentWidget;
             this._parentWidget = null;
+            this._updateDefaultFocusedElementListener();
         } else {
             WebInspector.Widget.__assert(this._isRoot, "Removing non-root widget from DOM");
         }
@@ -425,7 +433,22 @@ WebInspector.Widget.prototype = {
      */
     setDefaultFocusedElement: function(element)
     {
+        if (this._defaultFocusedElement)
+            this._defaultFocusedElement.removeEventListener("focus", this._boundWasFocused);
         this._defaultFocusedElement = element;
+        this._updateDefaultFocusedElementListener();
+        if (this._defaultFocusedElement.ownerDocument.activeElement.isSelfOrDescendant(this._defaultFocusedElement))
+            this.wasFocused();
+    },
+
+    _updateDefaultFocusedElementListener: function()
+    {
+        if (!this._defaultFocusedElement)
+            return;
+        if (this._parentWidget)
+            this._defaultFocusedElement.addEventListener("focus", this._boundWasFocused, true);
+        else
+            this._defaultFocusedElement.removeEventListener("focus", this._boundWasFocused);

[luoe, 2016/09/08 20:48:56]

Should this and L437 also get useCapture == true, same as L449?

[einbinder, 2016/09/09 01:32:16]

This was removed in the next patch.

     },
 
     focus: function()
@@ -433,11 +456,24 @@ WebInspector.Widget.prototype = {
         var element = this._defaultFocusedElement;
         if (element && !element.isAncestor(this.element.ownerDocument.activeElement)) {
             WebInspector.setCurrentFocusElement(element);
+            this.wasFocused();
             return;
         }
 
-        if (this._children.length)
-            this._children[0].focus();
+        if (this._lastFocusedChild)
+            this._lastFocusedChild.focus();
+    },
+
+    /**
+     * @final
+     */
+    wasFocused: function()
+    {
+        var widget = this;
+        while (widget._parentWidget) {
+            widget._parentWidget._lastFocusedChild = widget;
+            widget = widget._parentWidget;
+        }
     },
 
     /**