Remove half of the checks for comparing two Obejcts

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 900e07ecdf9fa68a32540fc76be401d0b064a343..61b55aa49e644664dc91612c3510f2054e61d448 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -9231,10 +9231,9 @@ void HOptimizedGraphBuilder::VisitCompareOperation(CompareOperation* expr) {
         // Can we get away with map check and not instance type check?
         if (combined_type->IsClass()) {
           Handle<Map> map = combined_type->AsClass();
-          AddCheckMap(left, map);
-          AddCheckMap(right, map);
           HCompareObjectEqAndBranch* result =
-              New<HCompareObjectEqAndBranch>(left, right);
+              New<HCompareObjectEqAndBranch>(AddCheckMap(left, map),
+                                             AddCheckMap(right, map));
           if (FLAG_emit_opt_code_positions) {
             result->set_operand_position(zone(), 0, expr->left()->position());
             result->set_operand_position(zone(), 1, expr->right()->position());