Tooltip doesn't show when hovering over tree icon (microsoft#159663)

Fixes microsoft#159662

Author: alexr00

src/vs/workbench/browser/parts/views/media/views.css

@@ -136,7 +136,7 @@
 	display: block;
 }
 
-.customview-tree .monaco-list .monaco-list-row .custom-view-tree-node-item > .custom-view-tree-node-item-icon {
+.customview-tree .monaco-list .monaco-list-row .custom-view-tree-node-item > .custom-view-tree-node-item-resourceLabel > .custom-view-tree-node-item-icon {
 	background-size: 16px;
 	background-position: left center;
 	background-repeat: no-repeat;
@@ -150,16 +150,16 @@
 	-moz-osx-font-smoothing: grayscale;
 }
 
-.customview-tree .monaco-list .monaco-list-row .custom-view-tree-node-item>.custom-view-tree-node-item-icon.disabled {
+.customview-tree .monaco-list .monaco-list-row .custom-view-tree-node-item > .custom-view-tree-node-item-resourceLabel > .custom-view-tree-node-item-icon.disabled {
 	opacity: 0.6;
 }
 /* makes spinning icons square */
-.customview-tree .monaco-list .monaco-list-row .custom-view-tree-node-item > .custom-view-tree-node-item-icon.codicon.codicon-modifier-spin {
+.customview-tree .monaco-list .monaco-list-row .custom-view-tree-node-item > .custom-view-tree-node-item-resourceLabel > .custom-view-tree-node-item-icon.codicon.codicon-modifier-spin {
 	padding-left: 6px;
 	margin-left: -6px;
 }
 
-.customview-tree .monaco-list .monaco-list-row.selected .custom-view-tree-node-item > .custom-view-tree-node-item-icon.codicon {
+.customview-tree .monaco-list .monaco-list-row.selected .custom-view-tree-node-item > .custom-view-tree-node-item-resourceLabel > .custom-view-tree-node-item-icon.codicon {
 	color: currentColor !important;
 }
 

src/vs/workbench/browser/parts/views/treeView.ts

@@ -975,9 +975,8 @@ class TreeRenderer extends Disposable implements ITreeRenderer<ITreeItem, FuzzyS
 	renderTemplate(container: HTMLElement): ITreeExplorerTemplateData {
 		container.classList.add('custom-view-tree-node-item');
 
-		const icon = DOM.append(container, DOM.$('.custom-view-tree-node-item-icon'));
-
 		const resourceLabel = this.labels.create(container, { supportHighlights: true, hoverDelegate: this._hoverDelegate });
+		const icon = DOM.prepend(resourceLabel.element, DOM.$('.custom-view-tree-node-item-icon'));
 		const actionsContainer = DOM.append(resourceLabel.element, DOM.$('.actions'));
 		const actionBar = new ActionBar(actionsContainer, {
 			actionViewItemProvider: this.actionViewItemProvider