open editors: preview in italic

src/vs/workbench/parts/files/browser/media/explorerviewlet.css

@@ -88,6 +88,10 @@
 	font-size: .9em;
 }
 
+.explorer-viewlet .explorer-open-editors .monaco-tree .monaco-tree-row .open-editor.preview {
+	font-style: italic;
+}
+
 /* Theming */
 .vs-dark .monaco-workbench .explorer-viewlet .collapsible.header .action-close-all-files {
 	background: url("closeall_inverse.svg") center center no-repeat;

src/vs/workbench/parts/files/browser/views/openEditorsViewer.ts

@@ -36,6 +36,10 @@ export class OpenEditor {
 	public getDescription(): string {
 		return this.editor.getDescription();
 	}
+
+	public isPreview(): boolean {
+		return this.group.isPreview(this.editor);
+	}
 }
 
 export class DataSource implements tree.IDataSource {
@@ -126,6 +130,7 @@ export class Renderer implements tree.IRenderer {
 	}
 
 	private renderOpenEditor(tree: tree.ITree, editor: OpenEditor, templateData: IOpenEditorTemplateData): void {
+		editor.isPreview() ? dom.addClass(templateData.root, 'preview') : dom.removeClass(templateData.root, 'preview');
 		templateData.name.textContent = editor.getName();
 		templateData.description.textContent = editor.getDescription();
 	}