JDK 9 RFR of JDK-8032977: Add serial lint warning to build of jdk repository

[Tim Bell]

Hi Joe:

> With "cast", "static", and "overloads" lint warnings getting enabled 
> in the build in JDK 9, next up will be "serial". For a future time 
> when the library code is clean of serial warnings, work being tracked 
> under JDK-8032976 Fix serial lint warnings in client libraries , 
> please review the patch below to address
>
>     JDK-8032977: Add serial lint warning to build of jdk repository

Looks good to me.

Tim

> diff -r 295785eb9e65 make/Setup.gmk
> --- a/make/Setup.gmk    Tue Jan 28 17:22:07 2014 -0800
> +++ b/make/Setup.gmk    Wed Jan 29 10:09:18 2014 -0800
> @@ -27,7 +27,7 @@
>
>  # To build with all warnings enabled, do the following:
>  # make JAVAC_WARNINGS="-Xlint:all -Xmaxwarns 10000"
> -JAVAC_WARNINGS := 
> -Xlint:-unchecked,-deprecation,-overrides,auxiliaryclass,cast,classfile,dep-ann,divzero,empty,overloads,static,try,varargs 
> -Werror
> +JAVAC_WARNINGS := 
> -Xlint:-unchecked,-deprecation,-overrides,auxiliaryclass,cast,classfile,dep-ann,divzero,empty,overloads,serial,static,try,varargs 
> -Werror
>
>  # Any java code executed during a JDK build to build other parts of 
> the JDK must be
>  # executed by the bootstrap JDK (probably with -Xbootclasspath/p: ) 
> and for this
>