RFR (sh/8): Missing include in shenandoahOopClosures.cpp

[Roman Kennke]

This file came with Traversal GC, and is specific to sh/jdk8. It must 
include precompiled.hpp otherwise we get build failures on Windows.

diff -r 282516993f97 
src/share/vm/gc_implementation/shenandoah/shenandoahOopClosures.cpp
--- 
a/src/share/vm/gc_implementation/shenandoah/shenandoahOopClosures.cpp 
    Wed Nov 13 12:27:29 2019 +0100
+++ 
b/src/share/vm/gc_implementation/shenandoah/shenandoahOopClosures.cpp 
    Wed Nov 13 21:27:18 2019 +0100
@@ -21,6 +21,7 @@
   *
   */

+#include "precompiled.hpp"
  #include "gc_implementation/shenandoah/shenandoahHeap.inline.hpp"
  #include "gc_implementation/shenandoah/shenandoahOopClosures.hpp"
  #include "runtime/thread.hpp"


Ok?

Roman