RFR(L): 8199255: [TESTBUG] Open source VM testbase default methods tests

[Mikhailo Seledtsov]

Please review this change that will open source VM default method tests.
These tests have been used internally for a while, and are now being 
open sourced. Since this is not an creation of new tests, we would like 
to keep the changes during this review to a minimum required for open 
sourcing these tests, such as major issues and integration blockers. If 
you have other feedback regarding improvements to these tests, please 
file RFE(s) that will be addressed later in order of priority.

Here is what was done for this change:
   1. Moved the tests to OpenJDK repository to the specified directory 
location and structure.
   3. Updated Copyright statements accordingly.
   4. Updated "@library" statements accordingly.
   5. Updated TEST.groups and a HotSpot test make file

   JBS:    https://bugs.openjdk.java.net/browse/JDK-8199255
   Webrev: http://cr.openjdk.java.net/~mseledtsov/8199255.01/

   Testing:
       1. Ran the following tests on open-only repository and build, 
using "make run-test" (Linux-x64)
          vmTestbase_vm_defmeth
          All PASS

       2. Automated multip-platform test system (usual 4 platforms):
          - vmTestbase_vm_defmeth
          - hs-tier{1,2}
          In progress


Thank you,
Misha