Remove some compiling warning, please check it

[柳鲲鹏]

Hello all:
  I compile OpenJDK8 many times. I found some commen errors would be warned.
the attach files is modified. Please check it.
  Thanks.


Best regards.


Quantum Liu.

-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: AttachOperationFailedException.java
URL: <https://mail.openjdk.java.net/pipermail/jdk8u-dev/attachments/20210630/c543e181/AttachOperationFailedException-0001.java>
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: JapaneseEra.java
URL: <https://mail.openjdk.java.net/pipermail/jdk8u-dev/attachments/20210630/c543e181/JapaneseEra-0001.java>
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: SSLSessionContext.java
URL: <https://mail.openjdk.java.net/pipermail/jdk8u-dev/attachments/20210630/c543e181/SSLSessionContext-0001.java>
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: AbstractJSObject.java
URL: <https://mail.openjdk.java.net/pipermail/jdk8u-dev/attachments/20210630/c543e181/AbstractJSObject-0001.java>