ARM64: Enable shorten-64-to-32 warning

test/unittests/compiler/arm64/instruction-selector-arm64-unittest.cc

Index: test/unittests/compiler/arm64/instruction-selector-arm64-unittest.cc
diff --git a/test/unittests/compiler/arm64/instruction-selector-arm64-unittest.cc b/test/unittests/compiler/arm64/instruction-selector-arm64-unittest.cc
index 744f18f0bdb0bd7e4c133016d50f6f939417baeb..3ed52e0ba7f6182351ece11e358badbc06a22b6b 100644
--- a/test/unittests/compiler/arm64/instruction-selector-arm64-unittest.cc
+++ b/test/unittests/compiler/arm64/instruction-selector-arm64-unittest.cc
@@ -47,7 +47,7 @@ Node* BuildConstant(InstructionSelectorTest::StreamBuilder& m, MachineType type,
                     int64_t value) {
   switch (type) {
     case kMachInt32:
-      return m.Int32Constant(value);
+      return m.Int32Constant(static_cast<int32_t>(value));
       break;
 
     case kMachInt64: