A registry of Extensions.
register(extensionHandle: string,extensionEntry: ExtensionEntry,): Promise<void>
Register a specified ExtensionEntry with a specified Extension handle.
get(extensionHandle: string): Promise<Readonly<ExtensionEntry>>
Return the specified registered ExtensionEntry instance.
getExtensions(extensionPoint: string): Promise<ReadonlyMap<string, ExtensionEntry>>
Return ExtensionEntry instances for registered Extensions implementing the specified Extension Point.