Document view.type contribution

Fixes #105821

src/vs/workbench/api/browser/viewsExtensionPoint.ts

@@ -108,6 +108,18 @@ enum InitialVisibility {
 const viewDescriptor: IJSONSchema = {
 	type: 'object',
 	properties: {
+		type: {
+			markdownDescription: localize('vscode.extension.contributes.view.type', "Type of the the view. This can either be `tree` for a tree view based view or `webview` for a webview based view. The default is `tree`."),
+			type: 'string',
+			enum: [
+				'tree',
+				'webview',
+			],
+			markdownEnumDescriptions: [
+				localize('vscode.extension.contributes.view.tree', "The view is backed by a `TreeView` created by `createTreeView`."),
+				localize('vscode.extension.contributes.view.webview', "The view is backed by a `WebviewView` registered by `registerWebviewViewProvider`."),
+			]
+		},
 		id: {
 			description: localize('vscode.extension.contributes.view.id', 'Identifier of the view. This should be unique across all views. It is recommended to include your extension id as part of the view id. Use this to register a data provider through `vscode.window.registerTreeDataProviderForView` API. Also to trigger activating your extension by registering `onView:${id}` event to `activationEvents`.'),
 			type: 'string'