[assembler] Remove unnecessary cast.

src/s390/assembler-s390-inl.h

Index: src/s390/assembler-s390-inl.h
diff --git a/src/s390/assembler-s390-inl.h b/src/s390/assembler-s390-inl.h
index 3e7ff1061174d020871d2aeb8dea7d20bfeed6b5..a38c518deac4acd8365d02afd1e826ecd3cdf0fb 100644
--- a/src/s390/assembler-s390-inl.h
+++ b/src/s390/assembler-s390-inl.h
@@ -274,9 +274,9 @@ void RelocInfo::set_debug_call_address(Address target) {
   DCHECK(IsDebugBreakSlot(rmode()) && IsPatchedDebugBreakSlotSequence());
   Assembler::set_target_address_at(isolate_, pc_, host_, target);
   if (host() != NULL) {
-    Object* target_code = Code::GetCodeFromTargetAddress(target);
-    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(
-        host(), this, HeapObject::cast(target_code));
+    Code* target_code = Code::GetCodeFromTargetAddress(target);
+    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(host(), this,
+                                                                  target_code);
   }
 }