Remove redundant null checks in rxjava2 instrumentation (current Context is never null)

[mcculls]

Motivation

Simpler code, avoids unnecessarily storing root context - now matches the rxjava 3 instrumentation.

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Jira ticket: [PROJ-IDENT]

[datadog-datadog-prod-us1-2]

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 56.93% (-0.01%)

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: 0f72563 | Docs | Datadog PR Page | Give us feedback!}

[PerfectSlayer]

Looking good. Thanks for the follow up changes

[dd-octo-sts]

🟢 Java Benchmark SLOs — All performance SLOs passed

Suite	Status
Startup	🟢 pass

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	13.93 s	13.89 s	[-0.5%; +1.1%] (no difference)
startup:insecure-bank:tracing:Agent	12.92 s	12.95 s	[-0.7%; +0.3%] (no difference)
startup:petclinic:appsec:Agent	16.92 s	16.85 s	[-0.5%; +1.4%] (no difference)
startup:petclinic:iast:Agent	16.86 s	16.45 s	[-2.0%; +7.0%] (no difference)
startup:petclinic:profiling:Agent	16.80 s	16.86 s	[-1.7%; +0.9%] (no difference)
startup:petclinic:sca:Agent	16.73 s	16.76 s	[-1.2%; +0.8%] (no difference)
startup:petclinic:tracing:Agent	15.62 s	15.94 s	[-6.1%; +2.0%] (no difference)

Commit: 0f725637 · CI Pipeline · Benchmarking Platform UI

---

Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.

[pr-commenter]

Kafka / producer-benchmark

Parameters

	Baseline	Candidate
baseline_or_candidate	baseline	candidate
git_branch	mcculls/cleanup-java8-bridge	mcculls/cleanup-rxjava2-context
git_commit_date	1783434996	1783435050
git_commit_sha	291064f	0f72563

See matching parameters

	Baseline	Candidate
ci_job_date	1783436298	1783436298
ci_job_id	1837454066	1837454066
ci_pipeline_id	123279465	123279465
cpu_model	Intel(R) Xeon(R) Platinum 8259CL CPU @ 2.50GHz	Intel(R) Xeon(R) Platinum 8259CL CPU @ 2.50GHz
jdkVersion	11.0.25	11.0.25
jmhVersion	1.36	1.36
jvm	/usr/lib/jvm/java-11-openjdk-amd64/bin/java	/usr/lib/jvm/java-11-openjdk-amd64/bin/java
jvmArgs	-Dfile.encoding=UTF-8 -Djava.io.tmpdir=/go/src/github.com/DataDog/apm-reliability/dd-trace-java/platform/src/producer-benchmark/build/tmp/jmh -Duser.country=US -Duser.language=en -Duser.variant	-Dfile.encoding=UTF-8 -Djava.io.tmpdir=/go/src/github.com/DataDog/apm-reliability/dd-trace-java/platform/src/producer-benchmark/build/tmp/jmh -Duser.country=US -Duser.language=en -Duser.variant
vmName	OpenJDK 64-Bit Server VM	OpenJDK 64-Bit Server VM
vmVersion	11.0.25+9-post-Ubuntu-1ubuntu122.04	11.0.25+9-post-Ubuntu-1ubuntu122.04

Summary

Found 0 performance improvements and 0 performance regressions! Performance is the same for 3 metrics, 0 unstable metrics.

See unchanged results

scenario	Δ mean throughput
scenario:not-instrumented/KafkaProduceBenchmark.benchProduce	same
scenario:only-tracing-dsm-disabled-benchmarks/KafkaProduceBenchmark.benchProduce	same
scenario:only-tracing-dsm-enabled-benchmarks/KafkaProduceBenchmark.benchProduce	unsure [-4582.157op/s; -398.459op/s] or [-3.142%; -0.273%]