src/vs/workbench/services/extensions/common/abstractExtensionService.ts/filterByExtensionHostKind
function filterByExtensionHostKind(extensions: IExtensionDescription[], runningLocation: Map<string, ExtensionRunningLocation | null>, desiredExtensionHostKind: ExtensionHostKind): IExtensionDescription[] {
	return _filterExtensions(extensions, ext => ext.identifier, runningLocation, extRunningLocation => extRunningLocation.kind === desiredExtensionHostKind);
}