refactor(tracing): Move propagate context method to traceHandle (#4319)

### Description
Move propagate context method to traceHandle.

### Link to the issue in case of a bug fix.
b/479039670

### Testing details
Existing unit tests & integration tests must pass.

### Any backward incompatible change? If so, please explain.
N/A

Author: thrivikram-karur-g

internal/fs/fs.go

@@ -1757,7 +1757,7 @@ func (fs *fileSystem) getInterruptlessContext(ctx context.Context) context.Conte
 		// When ignore interrupts config is set, we are creating a new context not
 		// cancellable by parent context.
 		newCtx := context.Background()
-		return tracing.MaybePropagateTraceContext(newCtx, ctx, fs.isTracingEnabled)
+		return fs.traceHandle.PropagateTraceContext(newCtx, ctx)
 	}
 
 	return ctx

internal/fs/tracing_test.go

@@ -83,6 +83,7 @@ func createTestFileSystemWithTraces(ctx context.Context, t *testing.T, ignoreInt
 			},
 		},
 		SequentialReadSizeMb: 200,
+		TraceHandle:          tracing.NewOTELTracer(),
 	}
 	server, err := fs.NewFileSystem(ctx, serverCfg)
 	require.NoError(t, err, "NewFileSystem")

tracing/noop_tracer.go

@@ -35,6 +35,11 @@ func (*noopTracer) EndSpan(span trace.Span) {}
 
 func (*noopTracer) RecordError(span trace.Span, err error) {}
 
+// Return the new context as it is as this is a no-op implementation
+func (*noopTracer) PropagateTraceContext(newCtx context.Context, _ context.Context) context.Context {
+	return newCtx
+}
+
 func NewNoopTracer() TraceHandle {
 	return new(noopTracer)
 }

tracing/otel_tracer.go

@@ -43,6 +43,11 @@ func (o *otelTracer) RecordError(span trace.Span, err error) {
 	span.SetStatus(codes.Error, err.Error())
 }
 
+func (o *otelTracer) PropagateTraceContext(newCtx context.Context, oldCtx context.Context) context.Context {
+	span := trace.SpanFromContext(oldCtx)
+	return trace.ContextWithSpan(newCtx, span)
+}
+
 func NewOTELTracer() TraceHandle {
 	return &otelTracer{
 		tracer: otel.Tracer(name),

tracing/trace_handle.go

@@ -20,6 +20,8 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
+const name = "cloud.google.com/gcsfuse"
+
 // TraceHandle provides an interface for recording traces, trace links and everything related to tracing. This allows easier switching between various trace-implementations, especially with a custom no-op tracer.
 type TraceHandle interface {
 	// Start a span with a given name & context
@@ -33,4 +35,7 @@ type TraceHandle interface {
 
 	// Record an error on the span for export in case of failure
 	RecordError(span trace.Span, err error)
+
+	// A handle interface method to retain relevant span data in new context from the older context
+	PropagateTraceContext(newCtx context.Context, oldCtx context.Context) context.Context
 }