[runtime] Avoid @@isConcatSpreadable lookup for fast path Array.prototype.concat

src/crankshaft/ia32/lithium-codegen-ia32.cc

Index: src/crankshaft/ia32/lithium-codegen-ia32.cc
diff --git a/src/crankshaft/ia32/lithium-codegen-ia32.cc b/src/crankshaft/ia32/lithium-codegen-ia32.cc
index ee8317f2d55f38f24d98a3ef53f5fba8d60af3de..7fa3f4bd9c4bf89faa1c90ac74c3a9a87db9e3b5 100644
--- a/src/crankshaft/ia32/lithium-codegen-ia32.cc
+++ b/src/crankshaft/ia32/lithium-codegen-ia32.cc
@@ -3045,11 +3045,12 @@ void LCodeGen::DoLoadKeyedFixedArray(LLoadKeyed* instr) {
     __ j(not_equal, &done);
     if (info()->IsStub()) {
       // A stub can safely convert the hole to undefined only if the array
-      // protector cell contains (Smi) Isolate::kArrayProtectorValid. Otherwise
+      // protector cell contains (Smi) Isolate::kArrayElementsProtectorValid.
+      // Otherwise
       // it needs to bail out.
-      __ mov(result, isolate()->factory()->array_protector());
+      __ LoadRoot(result, Heap::kArrayElementsProtectorRootIndex);
       __ cmp(FieldOperand(result, PropertyCell::kValueOffset),
-             Immediate(Smi::FromInt(Isolate::kArrayProtectorValid)));
+             Immediate(Smi::FromInt(Isolate::kArrayElementsProtectorValid)));
       DeoptimizeIf(not_equal, instr, Deoptimizer::kHole);
     }
     __ mov(result, isolate()->factory()->undefined_value());