src/vs/workbench/api/common/extHostExtensionService.ts/filterExtensions
function filterExtensions(globalRegistry: ExtensionDescriptionRegistry, desiredExtensions: Set<string>): IExtensionDescription[] {
	return globalRegistry.getAllExtensionDescriptions().filter(
		extension => desiredExtensions.has(ExtensionIdentifier.toKey(extension.identifier))
	);
}