RFR: 8281728: Redundant null check in LineNumberInputStream.read

[Andrey Turbanov]

At start of method `b` is already checked for null.

https://github.com/openjdk/jdk/blob/178b962e01cc6c150442bf41dc6bd199caff0042/src/java.base/share/classes/java/io/LineNumberInputStream.java#L129-L131

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Commit messages:
 - [PATCH] Remove redundant null check in LineNumberInputStream.read

Changes: https://git.openjdk.java.net/jdk/pull/7409/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7409&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8281728
  Stats: 4 lines in 1 file changed: 0 ins; 2 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7409.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7409/head:pull/7409

PR: https://git.openjdk.java.net/jdk/pull/7409