Upgrade V8 to 5.1.281.57  DO NOT MERGE

FPIIM-449

Change-Id: Id981b686b4d587ac31697662eb98bb34be42ad90
(cherry picked from commit 3b9bc31999c9787eb726ecdbfd5796bfdec32a18)
diff --git a/test/cctest/test-sampler-api.cc b/test/cctest/test-sampler-api.cc
index 2cc15f8..e2c1c25 100644
--- a/test/cctest/test-sampler-api.cc
+++ b/test/cctest/test-sampler-api.cc
@@ -71,6 +71,12 @@
         simulator_->get_register(v8::internal::Simulator::sp));
     state->fp = reinterpret_cast<void*>(
         simulator_->get_register(v8::internal::Simulator::fp));
+#elif V8_TARGET_ARCH_S390 || V8_TARGET_ARCH_S390X
+    state->pc = reinterpret_cast<void*>(simulator_->get_pc());
+    state->sp = reinterpret_cast<void*>(
+        simulator_->get_register(v8::internal::Simulator::sp));
+    state->fp = reinterpret_cast<void*>(
+        simulator_->get_register(v8::internal::Simulator::fp));
 #endif
   }