RFR [8]: Fix non-PCH builds

[Aleksey Shipilev]

Recent push with backports to sh/jdk8u started to break non-PCH builds. Fix:

diff -r 1e219f3b537f -r da9bd08703c8
src/share/vm/gc_implementation/shenandoah/shenandoahStrDedupTable.cpp
--- a/src/share/vm/gc_implementation/shenandoah/shenandoahStrDedupTable.cpp     Thu Oct 18 22:19:03
2018 +0200
+++ b/src/share/vm/gc_implementation/shenandoah/shenandoahStrDedupTable.cpp     Fri Oct 19 16:24:15
2018 +0200
@@ -32,6 +32,7 @@
 #include "memory/allocation.hpp"
 #include "runtime/atomic.hpp"
 #include "runtime/safepoint.hpp"
+#include "runtime/vmThread.hpp"

 const size_t  ShenandoahStrDedupTable::_min_size = (1 << 10);   // 1024
 const size_t  ShenandoahStrDedupTable::_max_size = (1 << 24);   // 16777216

Testing: Linux x86_64 build

Thanks,
-Aleksey