RFR: 8267670: Update java.io, java.math, and java.text to use switch expressions [v7]

[Patrick Concannon]

> Hi,
> 
> Could someone please review my code for updating the code in the `java.io`, `java.math`, and `java.text` packages to make use of the switch expressions?
> 
> Kind regards,
> Patrick

Patrick Concannon has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains eight additional commits since the last revision:

 - Merge remote-tracking branch 'origin/master' into JDK-8267670
 - 8267670: Added missing brace
 - Merge remote-tracking branch 'origin/master' into JDK-8267670
 - 8267670: Removed trailing whitespace
 - 8267670: Remove redundant code from switch
 - 8267670: Updated code to use yield
 - Merge remote-tracking branch 'origin/master' into JDK-8267670
 - 8267670: Update java.io, java.math, and java.text to use switch expressions

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/4182/files
  - new: https://git.openjdk.java.net/jdk/pull/4182/files/a0dfbeba..57184fbf

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4182&range=06
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4182&range=05-06

  Stats: 29 lines in 1 file changed: 17 ins; 5 del; 7 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4182.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4182/head:pull/4182

PR: https://git.openjdk.java.net/jdk/pull/4182