RFR(M): 8233787: Break cycle in vm_version* includes

[Kim Barrett]

> On Nov 11, 2019, at 11:56 AM, Schmidt, Lutz <lutz.schmidt at sap.com> wrote:
> 
> Oh, oh,
> looks like I stepped into a beehive... Found JDK-8202579 and JDK-8145956 talking about the unwanted use of Abstract_VM_Version.
> 
> My intended change would not tackle that "mess", as you call it. But it would make potential future cleanups a little bit easier by ensuring all of hotspot code only includes vm_version.hpp. I'm in the process of modifying my initial change to reflect Kim's suggestions. I'll send it out Tuesday (hopefully), Wednesday the latest. 

JDK-7041262 was fixed a while ago, though I found that a new reference to Abstract_VM_Version
was recently added: https://bugs.openjdk.java.net/browse/JDK-8233943

I agree that JDK-8202579 looks like it might be easier to deal with after a change to break include cycles.
(BTW, I hadn’t noticed the include cycles before; good find!)