Improve views contribution point

- add required properties
- add default snippet
- use `markdownDescription` for markdown string

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

@@ -107,6 +107,8 @@ enum InitialVisibility {
 
 const viewDescriptor: IJSONSchema = {
 	type: 'object',
+	required: ['id', 'name'],
+	defaultSnippets: [{ body: { id: '${1:id}', name: '${2:name}' } }],
 	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`."),
@@ -121,7 +123,7 @@ const viewDescriptor: IJSONSchema = {
 			]
 		},
 		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:${id}` event to `activationEvents`.'),
+			markdownDescription: localize('vscode.extension.contributes.view.id', 'Identifier of the view. This should be unique across all views. It is recommended to include your extension id as part of the view id. Use this to register a data provider through `vscode.window.registerTreeDataProviderForView` API. Also to trigger activating your extension by registering `onView:${id}` event to `activationEvents`.'),
 			type: 'string'
 		},
 		name: {