Remove ineffectual context assignment (#2000)
Remove ineffectual context assignment (#2000)

Signed-off-by: Zhou Hao <f577ade201aa03d612c19915a089dc6084d45cd9@cn.fujitsu.com>
jaegertracing/jaeger,pavolloffay/jaeger,uber/jaeger,jaegertracing/jaeger,jaegertracing/jaeger,jpkrohling/jaeger,uber/jaeger,pavolloffay/jaeger,jpkrohling/jaeger,jaegertracing/jaeger,pavolloffay/jaeger,uber/jaeger,uber/jaeger,jpkrohling/jaeger,pavolloffay/jaeger,pavolloffay/jaeger,jpkrohling/jaeger,jpkrohling/jaeger,jaegertracing/jaeger