RFR: JDK10: JDK-8180334: Unable to build jaotc launcher on windows

[Kumar Srinivasan]

1. Added a comment in the LauncherCommon.gmk, fixed typo
2. Added checks for spurious EXTRA_JAVA_ARGS, both as
     compile time and runtime check, the latter for a good measure.

Thanks
Kumar

PS: Mandy,  could you please file a RFE for the jlink requirements and 
assign it to me.

>> On Jun 7, 2017, at 2:58 PM, Kumar Srinivasan <kumar.x.srinivasan at oracle.com> wrote:
>>
>> Hello,
>>
>> Please review the changes to fix  JDK-8180334,  essentially -DJAVA_ARGS exceeds
>> a Visual Studio C++ compiler limit, and this fix provides a way to specify
>> very long  string literals, by the build system.
>>
>> This also includes some minor and subtle simplifications and cleanups wrt.
>> the JAVA_ARGS and its handling.
>>
>> Thanks
>>
>> Webrev: http://cr.openjdk.java.net/~ksrini/8180334/webrev.00
>> JBS: https://bugs.openjdk.java.net/browse/JDK-8180334
> This is a reasonable short-term solution.  As we discussed, we should
> look into extending jlink to create the native launcher using @argfile
> in a future release.
>
> make/launcher/LauncherCommon.gmk
>
> +# EXTRA_JAVA_ARGS Processed into a -DEXTRA_JAVA_ARGS and is prependedi
>
> typo: s/prependedi/prepended
>
> src/java.base/share/native/launcher/main.c
>    It may help to detect if main_jargc == 0 but extra_jargc > 0 and exit with an error in case any bug in creating such a launcher.
>
> Mandy