src/vs/workbench/contrib/debug/browser/debugSession.ts/DebugSession/completions
class DebugSession:	async completions(frameId: number | undefined, threadId: number, text: string, position: Position, overwriteBefore: number, token: CancellationToken): Promise<DebugProtocol.CompletionsResponse | undefined> {
		if (!this.raw) {
			return Promise.reject(new Error(localize('noDebugAdapter', "No debugger available, can not send '{0}'", 'completions')));
		}
		const sessionCancelationToken = this.getNewCancellationToken(threadId, token);

		return this.raw.completions({
			frameId,
			text,
			column: position.column,
			line: position.lineNumber,
		}, sessionCancelationToken);
	}