[Devtools] Change logic of DataGrid's padding-left for grouping

third_party/WebKit/Source/devtools/front_end/data_grid/DataGrid.js

Index: third_party/WebKit/Source/devtools/front_end/data_grid/DataGrid.js
diff --git a/third_party/WebKit/Source/devtools/front_end/data_grid/DataGrid.js b/third_party/WebKit/Source/devtools/front_end/data_grid/DataGrid.js
index a71306fabcba2d4dd22a26454c11bdc58d53fb0e..a28510fc1b5f53a4d1d1201ab13d73804dffd299 100644
--- a/third_party/WebKit/Source/devtools/front_end/data_grid/DataGrid.js
+++ b/third_party/WebKit/Source/devtools/front_end/data_grid/DataGrid.js
@@ -1264,6 +1264,8 @@ DataGrid.DataGridNode = class extends Common.Object {
     this.nextSibling = null;
     /** @type {number} */
     this.disclosureToggleWidth = 10;
+    /** @type {?Element} */
+    this._disclosureCell = null;
 
     /** @type {boolean} */
     this.selectable = true;
@@ -1284,6 +1286,13 @@ DataGrid.DataGridNode = class extends Common.Object {
   }
 
   /**
+   * @return {?Element}
+   */
+  disclosureCell() {
+    return this._disclosureCell;
+  }
+
+  /**
    * @protected
    * @return {!Element}
    */
@@ -1570,9 +1579,8 @@ DataGrid.DataGridNode = class extends Common.Object {
       cell.classList.add(alignment);
 
     if (columnId === this.dataGrid.disclosureColumnId) {
+      this._disclosureCell = cell;
       cell.classList.add('disclosure');
-      if (this.leftPadding)
-        cell.style.setProperty('padding-left', this.leftPadding + 'px');
     }
 
     return cell;
@@ -1937,6 +1945,10 @@ DataGrid.DataGridNode = class extends Common.Object {
     if (!this.dataGrid || this._attached)
       return;
 
+    var leftPadding = this.leftPadding;
+    if (leftPadding && this._disclosureCell)
+      this._disclosureCell.style.setProperty('padding-left', leftPadding + 'px');
+
     this._attached = true;
 
     var previousNode = this.traversePreviousNode(true, true);