RFR: 8278016: Add compiler tests to tier{2,3}

[Aleksey Shipilev]

I have been looking at `hotspot:tier4` (catch-all not in lower tiers) run logs, and realized the whole bunch of compiler tests are running there.

Since `hotspot:tier4` runs a lot of `vmTestbase` tests, contributors seldom run it, as it takes many hours. Which means that many compiler tests are not running regularly for many contributors. But these tests are rather fast themselves and cover important compiler features.

We can properly add compiler tests to `tier{2,3}` to expose them on earlier tiers. The split logic between tiers is roughly: fast feature tests go into tier2, slower feature tests and debugging/printing stuff goes to tier3.

Sample times for new subgroups (think about this as "How much time they add to existing tiers"):


==============================
Test summary
==============================
   TEST                                              TOTAL  PASS  FAIL ERROR   
   jtreg:test/hotspot/jtreg:tier2_compiler             243   243     0     0   
==============================

real	2m16.518s
user	35m40.839s
sys	1m35.334s

==============================
Test summary
==============================
   TEST                                              TOTAL  PASS  FAIL ERROR   
   jtreg:test/hotspot/jtreg:tier3_compiler             132   132     0     0   
==============================

real	4m31.935s
user	71m54.617s
sys	2m13.073s

-------------

Commit messages:
 - Fix

Changes: https://git.openjdk.java.net/jdk/pull/6622/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=6622&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8278016
  Stats: 43 lines in 1 file changed: 43 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6622.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6622/head:pull/6622

PR: https://git.openjdk.java.net/jdk/pull/6622