IntelliJ/Java: Duplicate code -> ChunkedInputStream.advanceChunk

[jsoref]

Refactored as ChunkedInputStream.advanceChunk

This is for discussion.

Notes:

• Most commits were created by IntelliJ
• Individual commits are mostly self contained
• In general, most commits should not change program behavior at all

This is generally a subset of https://github.com/jsoref/jenkins/commits/java-cleanup-full

Proposed changelog entries

• Internal: Internal Java code cleanup

Submitter checklist

• JIRA issue is well described
• Changelog entry appropriate for the audience affected by the change (users or developer, depending on the change). Examples
  * Use the Internal: prefix if the change has no user-visible impact (API, test frameworks, etc.)
• Appropriate autotests or explanation to why this change has no tests
• For dependency updates: links to external changelogs and, if possible, full diffs

Desired reviewers

[oleg-nenashev]

Would be nice to follow the standard Java codestyle, but LGTM functionally, wice.
Approving since the code is readable

I plan to merge it tomorrow if no negative feedback