ES6 symbols: Implement Symbol intrinsic and basic functionality

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 319eb01457a080cc44c02bb92b67f9da3c6abc17..811dcc9ce8ee551104c7a0f461506495509f00e3 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -5903,7 +5903,13 @@ Condition LCodeGen::EmitTypeofIs(Label* true_label,
       __ cmp(input, factory()->null_value());
       __ j(equal, true_label);
     }
-    __ CmpObjectType(input, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE, input);
+    if (FLAG_harmony_symbols) {
+      __ CmpObjectType(input, SYMBOL_TYPE, input);
+      __ j(equal, true_label);
+      __ CmpInstanceType(input, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE);
+    } else {
+      __ CmpObjectType(input, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE, input);
+    }
     __ j(below, false_label);
     __ CmpInstanceType(input, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
     __ j(above, false_label);