RFR: 8256912: Zero builds fail after JDK-8255984

[Aleksey Shipilev]

This went through testing cracks, as JDK-8255796 was integrated at the same time. Zero x86_64 fails with:

In file included from /home/runner/work/jdk/jdk/jdk/src/hotspot/share/gc/shenandoah/shenandoahCollectionSet.hpp:30,
                 from /home/runner/work/jdk/jdk/jdk/src/hotspot/share/gc/shenandoah/heuristics/shenandoahAdaptiveHeuristics.cpp:28:

  348 | inline size_t get_live_data_bytes() const;
      | ^~~~~~~~~~~~~~~~~~~

  351 | inline size_t garbage() const;
      | ^~~~~~~

The fix is trivial: reinstating the `#include`-s.

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

Commit messages:
 - 8256912: Zero builds fail after JDK-8255984

Changes: https://git.openjdk.java.net/jdk/pull/1401/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1401&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8256912
  Stats: 2 lines in 1 file changed: 2 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1401.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1401/head:pull/1401

PR: https://git.openjdk.java.net/jdk/pull/1401