ES6 symbols: Implement Symbol intrinsic and basic functionality

src/arm/builtins-arm.cc

Index: src/arm/builtins-arm.cc
diff --git a/src/arm/builtins-arm.cc b/src/arm/builtins-arm.cc
index d17f393aaaa1ba2a5b5bf8961c3940bcb5943771..6a5f61fd1684ea3affda9d951eff675bd157c2d5 100644
--- a/src/arm/builtins-arm.cc
+++ b/src/arm/builtins-arm.cc
@@ -1044,9 +1044,13 @@ static void Generate_JSConstructStubHelper(MacroAssembler* masm,
 
     // If the type of the result (stored in its map) is less than
     // FIRST_SPEC_OBJECT_TYPE, it is not an object in the ECMA sense.
-    __ CompareObjectType(r0, r3, r3, FIRST_SPEC_OBJECT_TYPE);
+    __ CompareObjectType(r0, r1, r3, FIRST_SPEC_OBJECT_TYPE);
     __ b(ge, &exit);
 
+    // Symbols are "objects".
+    __ CompareInstanceType(r1, r3, SYMBOL_TYPE);
+    __ b(eq, &exit);
+
     // Throw away the result of the constructor invocation and use the
     // on-stack receiver as the result.
     __ bind(&use_receiver);