src/vs/workbench/api/common/extHostLanguageFeatures.ts/ExtHostLanguageFeatures/$provideSignatureHelp
class ExtHostLanguageFeatures:	$provideSignatureHelp(handle: number, resource: UriComponents, position: IPosition, context: extHostProtocol.ISignatureHelpContextDto, token: CancellationToken): Promise<extHostProtocol.ISignatureHelpDto | undefined> {
		return this._withAdapter(handle, SignatureHelpAdapter, adapter => adapter.provideSignatureHelp(URI.revive(resource), position, context, token), undefined, token);
	}