Request for reviews (XS): 6788376: allow to ignore unrecognized VM options

[Vladimir Kozlov]

http://webrev.invokedynamic.info/kvn/6788376/index.html

Fixed 6788376: allow to ignore unrecognized VM options

Problem:
Hotspot has flags which could be unavailable in different
versions (server vs client, product vs debug) of VM.
It complicates VM testing.

Solution:
Add new product flag -XX:+IgnoreUnrecognizedVMOptions.
By default it is off. It does not works with
options specified in a flags file (-XX:Flags=file).

Add the flag to the test compiler/6775880/Test.java
to run it with product VM (DeoptimizeALot flag is
the debug flag unavailable in product VM).

Reviewed by:
Fix verified (y/n): y

Other testing:
JPRT