[assembler] Remove unnecessary cast.

src/x87/assembler-x87-inl.h

Index: src/x87/assembler-x87-inl.h
diff --git a/src/x87/assembler-x87-inl.h b/src/x87/assembler-x87-inl.h
index 357c2c8fbe40dbf394ce559f890b9752d456359e..b175fd55db51d777d854497f65c1159d85ea8f4f 100644
--- a/src/x87/assembler-x87-inl.h
+++ b/src/x87/assembler-x87-inl.h
@@ -232,9 +232,9 @@ void RelocInfo::set_debug_call_address(Address target) {
   Address location = pc_ + Assembler::kPatchDebugBreakSlotAddressOffset;
   Assembler::set_target_address_at(isolate_, location, 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);
   }
 }