Review Request: 7141246 build-infra merge: Introduce new JVM_VARIANT* to control which kind of jvm gets built

[Erik Joelsson]

http://cr.openjdk.java.net/~erikj/7141246/webrev.01/ 
<http://cr.openjdk.java.net/%7Eerikj/7141246/webrev.01/>
267 lines changed: 119 ins; 40 del; 108 mod; 4676 unch

7141246 build-infra merge: Introduce new JVM_VARIANT* to control which 
kind of jvm gets built

The build-infra project is starting to move into jdk8. For the hotspot 
build to stay compatible with the changes, the variables used to control 
which kind of jvm gets built needs to be cleaned up. We propose the 
following scheme:

JVM_VARIANT={server,client,zero etc}
JVM_VARIANT_SERVER={true,false}
JVM_VARIANT_CLIENT={true,false}
etc.

With this scheme it becomes possible to choose any type of jvm, while 
the current scheme can't support only server on 32-bit platform.

Readability in makefile source is much improved with removal of double 
negations.

Backwards compatibility is kept by translating the old variables 
(ZERO_BUILD, BUILD_ONLY_CLIENT etc) to the new variables in make/defs.gmk.


Additional note: This change will not make all combinations valid or 
buildable. However, some previously impossible variations are now 
possible, most notably skipping client or kernel on 32-bit hosts.

/Erik