RFR: 8058176: [mlvm] tests should not allow code cache exhaustion [v5]

[Evgeny Nikitin]

> Another approach to the JDK-8058176 and #2440 - never allowing the tests hit CodeCache limits. The most significant consumer is the MH graph builder (the MHTransformationGen), whose consumption is now controlled. List of changes:
> 
> * Code cache size getters are added to WhiteBox;
> * MH sequences are now built with remaining Code cache size in mind (always let 2M clearance);
> * Dependencies on WhiteBox added for all affected tests;
> * The test cases in question un-problemlisted.
> 
> Testing: the whole vmTestbase/vm/mlvm/ in win-lin-mac x86.

Evgeny Nikitin has updated the pull request incrementally with one additional commit since the last revision:

  Extract allowances into constants

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2523/files
  - new: https://git.openjdk.java.net/jdk/pull/2523/files/6a3c4785..76b02724

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2523&range=04
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2523&range=03-04

  Stats: 6 lines in 1 file changed: 2 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2523.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2523/head:pull/2523

PR: https://git.openjdk.java.net/jdk/pull/2523