HBASE-26819 Minor code cleanup in and around RpcScheduler

[ndimiduk]

See compatibility discussion from #4173.

FYI @stoty

[Apache-HBase]

🎊 +1 overall

Vote	Subsystem	Runtime	Comment
+0 🆗	reexec	0m 50s	Docker mode activated.
		_ Prechecks _
+1 💚	dupname	0m 0s	No case conflicting files found.
+1 💚	hbaseanti	0m 0s	Patch does not have any anti-patterns.
+1 💚	@author	0m 0s	The patch does not contain any @author tags.
		_ master Compile Tests _
+1 💚	mvninstall	3m 12s	master passed
+1 💚	compile	2m 43s	master passed
+1 💚	checkstyle	0m 49s	master passed
+1 💚	spotbugs	1m 36s	master passed
		_ Patch Compile Tests _
+1 💚	mvninstall	2m 45s	the patch passed
+1 💚	compile	2m 24s	the patch passed
+1 💚	javac	2m 24s	the patch passed
+1 💚	checkstyle	0m 34s	hbase-server: The patch generated 0 new + 4 unchanged - 5 fixed = 4 total (was 9)
+1 💚	whitespace	0m 0s	The patch has no whitespace issues.
+1 💚	hadoopcheck	12m 35s	Patch does not cause any errors with Hadoop 3.1.2 3.2.2 3.3.1.
+1 💚	spotbugs	1m 38s	the patch passed
		_ Other Tests _
+1 💚	asflicense	0m 11s	The patch does not generate ASF License warnings.
		35m 13s

Subsystem	Report/Notes
Docker	ClientAPI=1.41 ServerAPI=1.41 base: https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/artifact/yetus-general-check/output/Dockerfile
GITHUB PR	#4192
Optional Tests	dupname asflicense javac spotbugs hadoopcheck hbaseanti checkstyle compile
uname	Linux 40bf53654aef 5.4.0-1025-aws #25~18.04.1-Ubuntu SMP Fri Sep 11 12:03:04 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/hbase-personality.sh
git revision	master / 1047194
Default Java	AdoptOpenJDK-1.8.0_282-b08
Max. process+thread count	60 (vs. ulimit of 30000)
modules	C: hbase-server U: hbase-server
Console output	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/console
versions	git=2.17.1 maven=3.6.3 spotbugs=4.2.2
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[Apache-HBase]

💔 -1 overall

Vote	Subsystem	Runtime	Comment
+0 🆗	reexec	0m 42s	Docker mode activated.
-0 ⚠️	yetus	0m 3s	Unprocessed flag(s): --brief-report-file --spotbugs-strict-precheck --whitespace-eol-ignore-list --whitespace-tabs-ignore-list --quick-hadoopcheck
		_ Prechecks _
		_ master Compile Tests _
+1 💚	mvninstall	3m 1s	master passed
+1 💚	compile	0m 40s	master passed
+1 💚	shadedjars	3m 46s	branch has no errors when building our shaded downstream artifacts.
+1 💚	javadoc	0m 25s	master passed
		_ Patch Compile Tests _
+1 💚	mvninstall	2m 45s	the patch passed
+1 💚	compile	0m 41s	the patch passed
+1 💚	javac	0m 41s	the patch passed
+1 💚	shadedjars	3m 40s	patch has no errors when building our shaded downstream artifacts.
+1 💚	javadoc	0m 23s	the patch passed
		_ Other Tests _
-1 ❌	unit	305m 22s	hbase-server in the patch failed.
		323m 21s

Subsystem	Report/Notes
Docker	ClientAPI=1.41 ServerAPI=1.41 base: https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/artifact/yetus-jdk11-hadoop3-check/output/Dockerfile
GITHUB PR	#4192
Optional Tests	javac javadoc unit shadedjars compile
uname	Linux 6c5d10481990 5.4.0-1054-aws #57~18.04.1-Ubuntu SMP Thu Jul 15 03:21:36 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/hbase-personality.sh
git revision	master / 1047194
Default Java	AdoptOpenJDK-11.0.10+9
unit	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/artifact/yetus-jdk11-hadoop3-check/output/patch-unit-hbase-server.txt
Test Results	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/testReport/
Max. process+thread count	3314 (vs. ulimit of 30000)
modules	C: hbase-server U: hbase-server
Console output	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/console
versions	git=2.17.1 maven=3.6.3
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[Apache-HBase]

💔 -1 overall

Vote	Subsystem	Runtime	Comment
+0 🆗	reexec	1m 21s	Docker mode activated.
-0 ⚠️	yetus	0m 3s	Unprocessed flag(s): --brief-report-file --spotbugs-strict-precheck --whitespace-eol-ignore-list --whitespace-tabs-ignore-list --quick-hadoopcheck
		_ Prechecks _
		_ master Compile Tests _
+1 💚	mvninstall	4m 4s	master passed
+1 💚	compile	1m 6s	master passed
+1 💚	shadedjars	5m 20s	branch has no errors when building our shaded downstream artifacts.
+1 💚	javadoc	0m 37s	master passed
		_ Patch Compile Tests _
+1 💚	mvninstall	3m 37s	the patch passed
+1 💚	compile	0m 58s	the patch passed
+1 💚	javac	0m 58s	the patch passed
+1 💚	shadedjars	5m 25s	patch has no errors when building our shaded downstream artifacts.
+1 💚	javadoc	0m 33s	the patch passed
		_ Other Tests _
-1 ❌	unit	413m 37s	hbase-server in the patch failed.
		438m 30s

Subsystem	Report/Notes
Docker	ClientAPI=1.41 ServerAPI=1.41 base: https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/artifact/yetus-jdk8-hadoop3-check/output/Dockerfile
GITHUB PR	#4192
Optional Tests	javac javadoc unit shadedjars compile
uname	Linux 0e8cf03694b3 5.4.0-90-generic #101-Ubuntu SMP Fri Oct 15 20:00:55 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
Build tool	maven
Personality	dev-support/hbase-personality.sh
git revision	master / 1047194
Default Java	AdoptOpenJDK-1.8.0_282-b08
unit	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/artifact/yetus-jdk8-hadoop3-check/output/patch-unit-hbase-server.txt
Test Results	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/testReport/
Max. process+thread count	2016 (vs. ulimit of 30000)
modules	C: hbase-server U: hbase-server
Console output	https://ci-hbase.apache.org/job/HBase-PreCommit-GitHub-PR/job/PR-4192/1/console
versions	git=2.17.1 maven=3.6.3
Powered by	Apache Yetus 0.12.0 https://yetus.apache.org

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