[foreign] RFR 8217369: jextract macro parser could avoid javac for simple macros

[Sundararajan Athijegannathan]

Please review.

Bug: https://bugs.openjdk.java.net/browse/JDK-8217369
Webrev: https://cr.openjdk.java.net/~sundar/8217369/webrev.00/

3 to 4s improvement on Python sample (13s to 9/10s on Mac). About 45% 
are simple int valued macros.

Thanks,
-Sundar