Update tabs structure

src/vs/vscode.proposed.d.ts

@@ -2325,12 +2325,11 @@ declare module 'vscode' {
 		readonly resource?: Uri;
 
 		/**
-		 * The identifier of the editor which the tab should contain, because
-		 * not all tabs represent editors this may be undefined.
-		 * This is equivalent to `viewType` for custom editors and notebooks.
+		 * The identifier of the view contained in the tab
+		 * This is equivalent to `viewType` for custom editors and `notebookType` for notebooks.
 		 * The built-in text editor has an id of 'default' for all configurations.
 		 */
-		readonly editorId?: string;
+		readonly viewId?: string;
 
 		/**
 		 * Whether or not the tab is currently active

src/vs/workbench/api/common/extHostEditorTabs.ts

@@ -15,7 +15,7 @@ export interface IEditorTab {
 	label: string;
 	viewColumn: ViewColumn;
 	resource?: vscode.Uri;
-	editorId?: string;
+	viewId?: string;
 	isActive: boolean;
 }
 
@@ -59,7 +59,7 @@ export class ExtHostEditorTabs implements IExtHostEditorTabs {
 				label: dto.label,
 				viewColumn: typeConverters.ViewColumn.to(dto.viewColumn),
 				resource: URI.revive(dto.resource),
-				editorId: dto.editorId,
+				viewId: dto.editorId,
 				isActive: dto.isActive
 			});
 		});