src/vs/workbench/api/common/extHostCustomEditors.ts/EditorProviderStore/addTextProvider
class EditorProviderStore:	public addTextProvider(viewType: string, extension: IExtensionDescription, provider: vscode.CustomTextEditorProvider): vscode.Disposable {
		return this.add(WebviewEditorType.Text, viewType, extension, provider);
	}