Updated: [11] RFR(M) 8184349: There should be some verification that EnableJVMCI is disabled if a GC not supporting JVMCI is selected

[Vladimir Kozlov]

http://cr.openjdk.java.net/~kvn/8184349/webrev.04/

I updated changes made back in May. I pushed CMS tests changes in 
separate fix 8202611.

The main fix is for JVMCI to check if GC is supported and exit VM with 
error if not [1]. It is called from Arguments::apply_ergo() after GC is 
selected in GCConfig::initialize().

In Arguments::check_vm_args_consistency() I added compiler flags reset 
in -Xint case when Interpreter only used.

ScavengeRootsInCode code for JVMCI is removed because the same code is 
executed already always in Arguments::parse() [2].

Added new Arguments::set_compiler_flags() called from apply_ergo() to 
combine all compiler flags ergo settings.

One test CheckCompileThresholdScaling.java was modified because scaling 
compiler threshold is skipped in Interpreter mode (-Xint).

Tested tier1,tier2,tier3-graal

Thanks,
Vladimir

[1] 
http://cr.openjdk.java.net/~kvn/8184349/webrev.04/src/hotspot/share/jvmci/jvmci_globals.cpp.udiff.html
[2] 
http://hg.openjdk.java.net/jdk/jdk/file/54fcaffa8fac/src/hotspot/share/runtime/arguments.cpp#l4111