Unable to set a specific traceId to the start span when using the OpenTelemetry API in Dart

[Hridhay0316]

Describe the bug
Unable to set a specific traceId to the start span when using the OpenTelemetry API in Dart

Steps to reproduce
1.Initialize the OpenTelemetry SDK and configure it with the necessary exporters.
2.Create a new span and attempt to set a specific traceId.
3.Start the span.
4.Observe the traceId of the started span in jeager

import 'package:opentelemetry/api.dart' as otel;
import 'package:opentelemetry/sdk.dart' as otel_sdk;

otel.Tracer? globalTracer;

void setupTracing() async {
final resource = otel_sdk.Resource(
[otel.Attribute.fromString('service.name', 'myproject')]);

final exporter = otel_sdk.CollectorExporter(
Uri.parse('Jeager URL'),
);
final processor = otel_sdk.BatchSpanProcessor(exporter);

final provider =
otel_sdk.TracerProviderBase(processors: [processor], resource: resource);

registerGlobalTracerProvider(provider);

globalTracer = provider.getTracer('myproject');

}

import 'package:opentelemetry/api.dart' as otel;

String? traceId = "8888bf2278369600d98ef29b6b628455";
String spanId =
"0000000000000001";
final spanContext = otel.SpanContext(
otel.TraceId.fromString(traceId),
otel.SpanId.fromString(spanId),
otel.TraceFlags.sampled,
otel.TraceState.empty(),
);
final spanKey = otel.ContextKey();
final newContext = otel.Context.current.setValue(spanKey, spanContext);
final span = globalTracer?.startSpan(
'fetchPolicyInfo',
context: newContext,
kind: otel.SpanKind.client,
);

What did you expect to see?
The span should start with the traceId set to the specific value provided

What did you see instead?
The span starts with a different traceId generated by the SDK, ignoring the provided traceId.

What version and what artifacts are you using?
Artifacts: opentelemetry
Version: v0.18.2
opentelemetry: ^0.18.2

Environment
Dart Version: 3.4.1
OS: Windows 11

[blakeroberts-wk]

The ContextKey you are using to set a value in the Context isn't the same key that tracer.startSpan() looks for when setting the span's parent. You will want to use contextWithSpanContext(context, spanContext).